Spacer Assembly for Drug Delivery Device

ABSTRACT

A drive assembly for a drug delivery system including a plunger member configured to engage and move a stopper within a container, a biasing member configured to move the plunger member, and an adjustable spacer assembly positioned between the plunger member and the stopper. The spacer assembly includes a spacer element attached to the stopper and at least one shim or includes a spacer element and a holder to which the spacer element is attached. The holder may be attached to the stopper and the spacer element may be attached to the holder by a threaded engagement. Also, a drug delivery system for injecting a medicament, the system including a container configured to receive a medicament, the container comprising a stopper configured to move within the container and a closure, a drive assembly as described above, and a needle actuator assembly.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. application Ser. No.16/160,231, filed Oct. 15, 2018, entitled Spacer Assembly for DrugDelivery Device”, which claims priority to U.S. Provisional ApplicationSer. No. 62/572,704, filed Oct. 16, 2017, entitled “Spacer Assembly forDrug Delivery Device”, the entire disclosures of each of which arehereby incorporated by reference.

BACKGROUND OF THE INVENTION Field of the Disclosure

The present disclosure relates generally to an injector device andmethod for delivering a fluid into the body of a patient by injection.

Description of the Related Art

Various types of automatic injection devices have been developed toallow drug solutions and other liquid therapeutic preparations to beadministered by untrained personnel or to be self-injected. Generally,these devices include a reservoir that is pre-filled with the liquidtherapeutic preparation, and some type of automatic needle-injectionmechanism that can be triggered by the user. When the volume of fluid ordrug to be administered is generally below a certain volume, such as 1mL, an auto-injector is typically used, which typically has an injectiontime of about 10 to 15 seconds. When the volume of fluid or drug to beadministered is above 1 mL, the injection time generally becomes longerresulting in difficulties for the patient to maintain contact betweenthe device and the target area of the patient's skin. Further, as thevolume of drug to be administered becomes larger, increasing the timeperiod for injection becomes desirable. The traditional method for adrug to be injected slowly into a patient is to initiate an IV andinject the drug into the patient's body slowly. Such a procedure istypically performed in a hospital or outpatient setting.

Certain devices allow for self-injection in a home setting and arecapable of gradually injecting a liquid therapeutic preparation into theskin of a patient. In some cases, these devices are small enough (bothin height and in overall size) to allow them to be “worn” by a patientwhile the liquid therapeutic preparation is being infused into thepatient. These devices typically include a pump or other type ofdischarge mechanism to force the liquid therapeutic preparation to flowout of a reservoir and into the injection needle. Such devices alsotypically include a valve or flow control mechanism to cause the liquidtherapeutic preparation to begin to flow at the proper time and atriggering mechanism to initiate the injection.

SUMMARY OF THE INVENTION

The present invention is directed to a drive assembly for a drugdelivery system comprising a plunger member configured to engage andmove a stopper within a container, the plunger member having a firstposition and a second position axially spaced from the first position, abiasing member configured to move the plunger member from the firstposition to the second position, and an adjustable spacer assemblypositioned between the plunger member and the stopper.

In one aspect, the spacer assembly may comprise a spacer elementattached to the stopper and at least one shim.

In another aspect, the spacer assembly may comprise a spacer element anda holder to which the spacer element is attached. The holder may beattached to the stopper and the spacer element may be attached to theholder by a threaded engagement. The threaded engagement may allowrotation of the spacer element relative to the holder when a torque isapplied to the spacer element to prohibit rotation of the spacer elementrelative to the holder when an axial force is applied to the spacerelement. The threads provided on the spacer element may extend in aradially outward direction. The threads provided on the spacer elementmay be angled such that application of an axial force to the spacerelement causes the threads to engage a sidewall of the holder.

When the spacer element is in a first position with respect to theholder, the spacer assembly has a first length in a longitudinaldirection, and when the when the spacer element is in a second positionwith respect to the holder, the spacer assembly has a second length inthe longitudinal direction, the first length being greater than thesecond length.

In another aspect, the spacer assembly may further comprise a flexibletab extending from the spacer element and a plurality of ratchet teethon a surface of the spacer holder. The flexible tab engages the ratchetteeth and the engagement of the flexible tab with the ratchet teethallows the spacer element to be rotated in a direction that threads thespacer element into the holder and prevents the spacer element fromrotating in a direction that removes the spacer element from the holder.

In another aspect, the spacer element is in a first position withrespect to the holder, the spacer assembly has a first length in alongitudinal direction, and when the when the spacer element is in asecond position with respect to the holder, the spacer assembly has asecond length in the longitudinal direction, the first length beinggreater than the second length.

In another aspect, the spacer element may comprise a first protrusionand the holder may comprise a second protrusion. When the spacer elementis in the first position with respect to the holder, the firstprotrusion is in contact with the second protrusion and the spacerassembly has the first length in the longitudinal direction, and whenthe spacer element is in a second position with respect to the holder,the first protrusion is not in contact with the second protrusion andthe spacer assembly has the second length in the longitudinal direction.

In another aspect, the spacer element may comprise an annular sidewalland the holder may comprise a sidewall and a central post. An exteriorsurface of the annular sidewall of the spacer element may be in threadedengagement with an interior surface of the sidewall of the holder and aninterior surface of the sidewall of the spacer may be in threadedengagement with an exterior surface of the central post. When thecentral post is a first position, movement of the spacer element withrespect to the holder is prohibited, and when the central post isaxially extended to a second position, the spacer element is free torotate with respect to the holder.

In another aspect, the spacer assembly may further comprise a lockingpin and the spacer element may further comprise a recess for receivingthe locking pin.

In another aspect, the spacer assembly may further comprise anexpandable container positioned within the spacer element and the holderbetween an upper proximal portion of the spacer element and a lowerbottom portion of the holder. Expansion or contraction of the expandablecontainer may cause the spacer element to move relative to the holder.

In another aspect, the spacer assembly may comprise a spacer elementfixed to the stopper and a plunger extension movably fixed to theplunger member. The plunger extension may be in threaded engagement withthe plunger member.

The present invention is also directed to a drug delivery system forinjecting a medicament, the system comprising a container configured toreceive a medicament, the container comprising a stopper configured tomove within the container and a closure, a drive assembly as describedabove, and a needle actuator assembly comprising a needle configured tobe placed in fluid communication with the container.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and advantages of thisdisclosure, and the manner of attaining them, will become more apparentand the disclosure itself will be better understood by reference to thefollowing descriptions of embodiments of the disclosure taken inconjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a drug delivery system according to oneaspect of the present invention.

FIG. 2 is a perspective, cross-sectional view of the drug deliverysystem of FIG. 1 according to one aspect of the present invention.

FIG. 3 is a front perspective, cross-sectional view of the drug deliverysystem of FIG. 1 according to one aspect of the present invention.

FIG. 4 is a top view of the drug delivery system of FIG. 1 according toone aspect of the present invention, showing a top portion of thehousing removed and the drug delivery system in a pre-use position.

FIG. 5 is a top, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing thedrug delivery system in a pre-use position.

FIG. 6 is a front, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing thedrug delivery system in a pre-use position.

FIG. 7 is a top view of the drug delivery system of FIG. 1 according toone aspect of the present invention, showing a top portion of thehousing removed and the drug delivery system in an initial actuationposition.

FIG. 8 is a top, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing thedrug delivery system in an initial actuation position.

FIG. 9 is a front, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing thedrug delivery system in an initial actuation position.

FIG. 10 is a top view of the drug delivery system of FIG. 1 according toone aspect of the present invention, showing a top portion of thehousing removed and the drug delivery system in a use position.

FIG. 11 is a top, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing thedrug delivery system in a use position.

FIG. 12 is a front, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing thedrug delivery system in a use position.

FIG. 13 is a top view of the drug delivery system of FIG. 1 according toone aspect of the present invention, showing a top portion of thehousing removed and the drug delivery system in a post-use position.

FIG. 14 is a top, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing thedrug delivery system in a post-use position.

FIG. 15A is a front, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing thedrug delivery system in a post-use position.

FIG. 15B is a front, cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing a padwith the drug delivery system in a pre-use position.

FIG. 15C is a perspective, cross-sectional view of the drug deliverysystem of FIG. 1 according to one aspect of the present invention,showing a pad with the drug delivery system in a pre-use position.

FIG. 15D is a perspective, cross-sectional view of the drug deliverysystem of FIG. 1 according to one aspect of the present invention,showing a pad with the drug delivery system in a pre-use position.

FIG. 16 is a partial cross-sectional view of the drug delivery system ofFIG. 1 according to one aspect of the present invention, showing a valveassembly.

FIG. 17 is a perspective view of a drive assembly for a drug deliverysystem according to one aspect of the present invention.

FIG. 18 is a cross-sectional view of the drive assembly of FIG. 17according to one aspect of the present invention, showing a pre-useposition of the drive assembly.

FIG. 19 is a cross-sectional view of the drive assembly of FIG. 17according to one aspect of the present invention, showing a use positionof the drive assembly.

FIG. 20 is a cross-sectional view of the drive assembly of FIG. 17according to one aspect of the present invention, showing a post-useposition of the drive assembly.

FIG. 21 is a perspective view of a plunger actuation member of the driveassembly of FIG. 17 according to one aspect of the present invention.

FIG. 22 is a perspective view of a first plunger member of the driveassembly of FIG. 17 according to one aspect of the present invention.

FIG. 23 is a perspective view of a plunger actuation member and firstplunger member of the drive assembly of FIG. 17 according to one aspectof the present invention, showing the plunger actuation member engagedwith the first plunger member.

FIG. 24 is a perspective view of a plunger actuation member and firstplunger member of the drive assembly of FIG. 17 according to one aspectof the present invention, showing the plunger actuation memberdisengaged from the first plunger member.

FIG. 25 is a perspective view of a plunger actuation member and firstplunger member of the drive assembly of FIG. 17 according to one aspectof the present invention, showing the plunger actuation memberdisengaged from and axially displaced relative to the first plungermember.

FIG. 26 is a front view of a first plunger member and a second plungermember of the drive assembly of FIG. 17 according to one aspect of thepresent invention.

FIG. 27 is a top view of a drive assembly for a drug delivery systemaccording to a further aspect of the present invention.

FIG. 28 is a perspective view of the drive assembly of FIG. 27 accordingto one aspect of the present invention.

FIG. 29 is a cross-sectional view of the drive assembly of FIG. 27according to one aspect of the present invention, showing a pre-useposition of the drive assembly.

FIG. 30 is a perspective view of the drive assembly of FIG. 27 accordingto one aspect of the present invention, showing the drive assemblyreceived by a bottom portion of a housing.

FIG. 31 is a perspective view of the housing of FIG. 30 according to oneaspect of the present invention.

FIG. 32 is a top view of the drive assembly of FIG. 27 according to oneaspect of the present invention, showing engagement of the driveassembly with a portion of a needle actuator in an initial actuationposition of the drive assembly.

FIG. 33 is an enlarged perspective view of the drive assembly of FIG. 27according to one aspect of the present invention, showing engagement ofthe drive assembly with a portion of a needle actuator in an initialactuation position of the drive assembly.

FIG. 34 is a front view of a needle actuator assembly according to oneaspect of the present invention.

FIG. 35 is a left side perspective view of a needle shuttle of theneedle actuator assembly of FIG. 34 according to one aspect of thepresent invention.

FIG. 36 is a right side perspective view of a needle shuttle of theneedle actuator assembly of FIG. 34 according to one aspect of thepresent invention.

FIG. 37A is a front view of the needle actuator assembly of FIG. 34according to one aspect of the present invention, showing the needleactuator assembly in a pre-use position.

FIG. 37B is a front view of the needle actuator assembly of FIG. 34according to one aspect of the present invention, showing the needleactuator assembly in a use position.

FIG. 37C is a front view of the needle actuator assembly of FIG. 34according to one aspect of the present invention, showing the needleactuator assembly in an initial post-use position.

FIG. 37D is a front view of the needle actuator assembly of FIG. 34according to one aspect of the present invention, showing the needleactuator assembly in a post-use position.

FIG. 38A is a perspective view of the needle actuator assembly of FIG.34 according to one aspect of the present invention, showing the needleactuator assembly in a use position.

FIG. 38B is a perspective view of the needle actuator assembly of FIG.34 according to one aspect of the present invention, showing the needleactuator assembly in an initial post-use position.

FIG. 39 is a perspective view of an actuator button and the needleactuator assembly of FIG. 34 according to one aspect of the presentinvention, showing the needle actuator assembly in an initial post-useposition.

FIG. 40A is a cross-sectional view of an actuator button and the needleactuator assembly of FIG. 34 according to one aspect of the presentinvention, showing the needle actuator assembly in an initial post-useposition.

FIG. 40B is a perspective view of an actuator button and the needleactuator assembly of FIG. 34 according to one aspect of the presentinvention, showing the needle actuator assembly in a post-use position.

FIG. 41 is a perspective view of a drive assembly for a drug deliverysystem according to a further aspect of the present invention.

FIG. 42 is a perspective view of the drive assembly of FIG. 41 accordingto one aspect of the present invention, showing a top portion of ahousing removed.

FIG. 43 is a cross-sectional view of the drive assembly of FIG. 41according to one aspect of the present invention.

FIG. 44 is a perspective view of the drive assembly of FIG. 41 accordingto one aspect of the present invention.

FIG. 45 is a cross-sectional view of the drive assembly of FIG. 41according to one aspect of the present invention, showing the driveassembly in a pre-use position.

FIG. 46 is a cross-sectional view of the drive assembly of FIG. 41according to one aspect of the present invention, showing the driveassembly in a pre-use position.

FIG. 47 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in a pre-useposition.

FIG. 48 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in aninitial actuation position.

FIG. 49 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in aninitial actuation position.

FIG. 50 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly an initialactuation position.

FIG. 51 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in a useposition.

FIG. 52 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in a useposition.

FIG. 53 is a cross-sectional view of the drive assembly of FIG. 41according to one aspect of the present invention, showing the driveassembly in a use position.

FIG. 54 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in a useposition.

FIG. 55 is a cross-sectional view of the drive assembly of FIG. 41according to one aspect of the present invention, showing the driveassembly in a use position.

FIG. 56 is a cross-sectional view of the drive assembly of FIG. 41according to one aspect of the present invention, showing the driveassembly in a use position.

FIG. 57 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in a useposition.

FIG. 58 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in aninitial post-use position.

FIG. 59 is a perspective view of the drive assembly of FIG. 41 accordingto one aspect of the present invention, showing the drive assembly in aninitial post-use position.

FIG. 60 is a top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in apost-use position.

FIG. 61 top view of the drive assembly of FIG. 41 according to oneaspect of the present invention, showing the drive assembly in apost-use position.

FIG. 62 is a cross-sectional view of the drive assembly of FIG. 41according to one aspect of the present invention, showing the driveassembly in a pre-use position.

FIG. 63 is a cross-sectional view of the drive assembly of FIG. 41according to one aspect of the present invention, showing the driveassembly in a use position.

FIG. 64 is a perspective view of a drive assembly according to a furtheraspect of the present invention.

FIG. 65A is a front view of a needle actuator assembly according to oneaspect of the present invention, showing the needle actuator assembly ina use position.

FIG. 65B is a front view of the needle actuator assembly of FIG. 65Aaccording to one aspect of the present invention, showing the needleactuator assembly in a use position.

FIG. 65C is a front view of the needle actuator assembly of FIG. 65Aaccording to one aspect of the present invention, showing the needleactuator assembly in an initial post-use position.

FIG. 65D is a front view of the needle actuator assembly of FIG. 65Aaccording to one aspect of the present invention, showing the needleactuator assembly in a post-use position.

FIG. 65E is a front view of the needle actuator assembly of FIG. 65Aaccording to one aspect of the present invention, showing the needleactuator assembly in a pre-use position.

FIG. 65F is a cross-sectional view of the needle actuator assembly ofFIG. 65A according to one aspect of the present invention, showing theneedle actuator assembly in a pre-use position.

FIG. 65G is a front view of the needle actuator assembly of FIG. 65Aaccording to one aspect of the present invention, showing the needleactuator assembly in a pre-use position with a button actuator axiallydisplaced.

FIG. 65H is a cross-sectional view of the needle actuator assembly ofFIG. 65A according to one aspect of the present invention, showing theneedle actuator assembly in a pre-use position with a button actuatoraxially displaced.

FIG. 66 is a perspective view of a button spring of the needle actuatorassembly of FIG. 65A according to one aspect of the present invention.

FIG. 67 is a perspective view of an actuator button of the needleactuator assembly of FIG. 65A according to one aspect of the presentinvention.

FIG. 68A is a cross-sectional view of a button spring and actuatorbutton of the needle actuator assembly of FIG. 65A according to oneaspect of the present invention.

FIG. 68B is a perspective view of an actuator button of the needleactuator assembly of FIG. 65A according to a further aspect of thepresent invention.

FIG. 68C is a bottom view of an actuator button of the needle actuatorassembly of FIG. 65A according to a further aspect of the presentinvention.

FIG. 68D is a front view of an actuator button of the needle actuatorassembly of FIG. 65A according to a further aspect of the presentinvention.

FIG. 68E is a top view of an actuator button of the needle actuatorassembly of FIG. 65A according to a further aspect of the presentinvention, showing the actuator button in a pre-use position.

FIG. 68F is a front view of an actuator button of the needle actuatorassembly of FIG. 65A according to a further aspect of the presentinvention, showing the actuator button in a pre-use position.

FIG. 68G is a top view of an actuator button of the needle actuatorassembly of FIG. 65A according to a further aspect of the presentinvention, showing the actuator button in a use position.

FIG. 68H is a front view of an actuator button of the needle actuatorassembly of FIG. 65A according to a further aspect of the presentinvention, showing the actuator button in a use position.

FIG. 69 is a top view of an actuator button of the needle actuatorassembly of FIG. 65A according to one aspect of the present invention.

FIG. 70 is a perspective view of a restriction member according to oneaspect of the present invention.

FIG. 71 is a front view of a spacer assembly for a drug delivery systemaccording to a further aspect of the present invention.

FIG. 72 is a perspective view of a drive assembly for a drug deliverysystem according to one aspect of the present invention.

FIG. 73 is a perspective view of the drive assembly of FIG. 72 accordingto one aspect of the present invention, showing a top portion of ahousing removed.

FIG. 74 is a cross-sectional view of the drive assembly of FIG. 72according to one aspect of the present invention, showing a pre-useposition of the drive assembly.

FIG. 75 is an enlarged cross-sectional view of the drive assembly ofFIG. 72 according to one aspect of the present invention, showing apre-use position of the drive assembly.

FIG. 76 is a top view of a biasing member of the drive assembly of FIG.72 according to one aspect of the present invention.

FIG. 77 is a perspective view of the drive assembly of FIG. 72 accordingto one aspect of the present invention, showing a restriction memberengaged with the drive assembly.

FIG. 78 is a perspective view of a drive assembly for a drug deliverysystem according to one aspect of the present invention.

FIG. 79 is a perspective view of the drive assembly of FIG. 78 accordingto one aspect of the present invention, showing a pre-use position ofthe drive assembly.

FIG. 80 is a cross-sectional view of the drive assembly of FIG. 78according to one aspect of the present invention.

FIG. 81 is a perspective view of the drive assembly of FIG. 78 accordingto one aspect of the present invention, showing a post-use position ofthe drive assembly.

FIG. 82 is a cross-sectional view of the drive assembly of FIG. 78according to one aspect of the present invention, showing a pre-useposition of the drive assembly.

FIG. 83 is a front view of the drive assembly of FIG. 78 according toone aspect of the present invention, showing a use position of the driveassembly.

FIG. 84A is a schematic view of a drive assembly according to one aspectof the present invention, showing the drive assembly in a pre-useposition.

FIG. 84B is a schematic view of the drive assembly of FIG. 84A accordingto one aspect of the present invention, showing the drive assembly in ause position.

FIG. 84C is a schematic view of the drive assembly of FIG. 84A accordingto one aspect of the present invention, showing the drive assembly in ause position.

FIG. 84D is a schematic view of the drive assembly of FIG. 84A accordingto one aspect of the present invention, showing the drive assembly in ause position.

FIG. 84E is a schematic view of the drive assembly of FIG. 84A accordingto one aspect of the present invention, showing the drive assembly in ause position.

FIG. 84F is a schematic view of the drive assembly of FIG. 84A accordingto one aspect of the present invention, showing the drive assembly in apost-use position.

FIG. 84G is a schematic view of the drive assembly of FIG. 84A accordingto one aspect of the present invention, showing the drive assembly in apost-use position.

FIG. 85 is a perspective view of a spacer assembly for a drug deliverysystem according to one aspect of the present invention, showing anassembled, pre-use position of the spacer assembly.

FIG. 86 is a perspective view of the spacer assembly of FIG. 85according to one aspect of the present invention, showing a use positionof the spacer assembly.

FIG. 87 is a perspective view of the spacer assembly of FIG. 85according to one aspect of the present invention, showing an initialpost-use position of the spacer assembly.

FIG. 88 is a top view of a spacer assembly for a drug delivery systemaccording to one aspect of the present invention.

FIG. 89 is a perspective view of the spacer assembly of FIG. 88according to one aspect of the present invention.

FIG. 90 is a cross-sectional view of the spacer assembly of FIG. 88according to one aspect of the present invention.

FIG. 91 is a perspective view of a spacer assembly for a drug deliverysystem according to a further aspect of the present invention.

FIG. 92 is a perspective view of a spacer assembly for a drug deliverysystem according to another aspect of the present invention.

FIG. 93A is a cross-sectional view of the spacer assembly of FIG. 92according to one aspect of the present invention, showing a pre-assemblyposition of the spacer assembly.

FIG. 93B is a cross-sectional view of the spacer assembly of FIG. 92according to one aspect of the present invention, showing an assembledposition of the spacer assembly.

FIG. 94 is a perspective view of a spacer assembly for a drug deliverysystem according to one aspect of the present invention.

FIG. 95 is a front view of the spacer assembly of FIG. 94 according toone aspect of the present invention.

FIG. 96 is a cross-sectional view of the spacer assembly of FIG. 94according to one aspect of the present invention.

FIG. 97 is a perspective view of the spacer assembly of FIG. 94according to one aspect of the present invention, showing a shimremoved.

FIG. 98 is a perspective view of a fixed spacer of the spacer assemblyof FIG. 94 according to one aspect of the present invention.

FIG. 99 is a perspective view of an adjustable spacer of the spacerassembly of FIG. 94 according to one aspect of the present invention.

FIG. 100 is a perspective view of a shim of the spacer assembly of FIG.94 according to one aspect of the present invention.

FIG. 101 is a cross-sectional view of a spacer assembly having a singleshim according to one aspect of the present invention.

FIG. 102 is a cross-sectional view of the spacer assembly of FIG. 101having multiple shims according to one aspect of the present invention.

FIG. 103 is a cross-sectional view a set of shims for use with thespacer assembly of FIG. 101 according to one aspect of the presentinvention.

FIG. 104 is a cross-sectional view of a spacer assembly according to oneaspect of the present invention.

FIG. 105 is a cross-sectional view of a spacer assembly according to oneaspect of the present invention.

FIG. 106 is a cross-sectional view of a spacer assembly according to oneaspect of the present invention.

FIG. 107 is a cross-sectional view of a spacer assembly according to oneaspect of the present invention.

FIG. 108 is a cross-sectional view of a spacer assembly according to oneaspect of the present invention.

FIG. 109 is a cross-sectional view of a spacer assembly shown in a firstposition according to one aspect of the present invention.

FIG. 110 is a cross-sectional view of the spacer assembly of FIG. 109shown in a second position according to one aspect of the presentinvention.

FIG. 111 is a cross-sectional view of a spacer assembly according to oneaspect of the present invention.

FIG. 112 is a magnified cross-sectional view of the indicated portion ofthe spacer assembly of FIG. 111 according to one aspect of the presentinvention.

FIG. 113 is a cross-sectional view of a spacer assembly shown in a firstposition according to one aspect of the present invention.

FIG. 114 is a cross-sectional view of the spacer assembly of FIG. 113shown in a second position according to one aspect of the presentinvention.

FIG. 115A is a cross-sectional view of a first step in the assembly ofthe spacer assembly of FIG. 113 according to one aspect of the presentinvention.

FIG. 115B is a cross-sectional view of a second step in the assembly ofthe spacer assembly of FIG. 113 according to one aspect of the presentinvention.

FIG. 115C is a cross-sectional view of a first step in the assembly ofthe spacer assembly of FIG. 113 according to one aspect of the presentinvention.

FIG. 116 is a cross-sectional view of a spacer assembly before theinsertion of the locking pin according to one aspect of the presentinvention.

FIG. 117 is a cross-sectional view of a spacer assembly of FIG. 116after the insertion of the locking pin according to one aspect of thepresent invention.

FIG. 118 is a cross-sectional view of a spacer assembly according to oneaspect of the present invention.

FIG. 119 is a cross-sectional view of an adjustable plunger assemblyaccording to one aspect of the present invention.

The exemplifications set out herein illustrate exemplary aspects of thedisclosure, and such exemplifications are not to be construed aslimiting the scope of the disclosure in any manner.

DETAILED DESCRIPTION

The following description is provided to enable those skilled in the artto make and use the described embodiments contemplated for carrying outthe invention. Various modifications, equivalents, variations, andalternatives, however, will remain readily apparent to those skilled inthe art. Any and all such modifications, variations, equivalents, andalternatives are intended to fall within the spirit and scope of thepresent invention.

For purposes of the description hereinafter, the terms “upper”, “lower”,“right”, “left”, “vertical”, “horizontal”, “top”, “bottom”, “lateral”,“longitudinal”, and derivatives thereof shall relate to the invention asit is oriented in the drawing figures. However, it is to be understoodthat the invention may assume various alternative variations, exceptwhere expressly specified to the contrary. It is also to be understoodthat the specific devices illustrated in the attached drawings, anddescribed in the following specification, are simply exemplaryembodiments of the invention. Hence, specific dimensions and otherphysical characteristics related to the embodiments disclosed herein arenot to be considered as limiting.

Referring to FIGS. 1-16, a drug delivery system 10 according to oneaspect of the present invention includes a drive assembly 12, acontainer 14, a valve assembly 16, and a needle actuator assembly 18.The drive assembly 12, the container 14, the valve assembly 16, and theneedle actuator assembly 18 are at least partially positioned within ahousing 20. The housing 20 includes a top portion 22 and a bottomportion 24, although other suitable arrangements for the housing 20 maybe utilized. In one aspect, the drug delivery system 10 is an injectordevice configured to be worn or secured to a user and to deliver apredetermined dose of a medicament provided within the container 14 viainjection into the user. The system 10 may be utilized to deliver a“bolus injection” where a medicament is delivered within a set timeperiod. The medicament may be delivered over a time period of up to 45minutes, although other suitable injection amounts and durations may beutilized. A bolus administration or delivery can be carried out withrate controlling or have no specific rate controlling. The system 10 maydeliver the medicament at a fixed pressure to the user with the ratebeing variable. The general operation of the system 10 is describedbelow in reference to FIGS. 1-16 with the specifics of the driveassembly 12, needle actuator assembly 18, and other features of thesystem 10, discussed below in connection with FIGS. 17-93.

Referring again to FIGS. 1-16, the system 10 is configured to operatethrough the engagement of an actuation button 26 by a user, whichresults in a needle 28 of the needle assembly 18 piercing the skin of auser, the actuation of the drive assembly 12 to place the needle 28 influid communication with the container 14 and to expel fluid ormedicament from the container 14, and the withdrawal of the needle 28after injection of the medicament is complete. The general operation ofa drug delivery system is shown and described in InternationalPublication Nos. 2013/155153 and 2014/179774, which are herebyincorporated by reference in their entirety. The housing 20 of thesystem 10 includes an indicator window 30 for viewing an indicatorarrangement 32 configured to provide an indication to a user on thestatus of the system 10 and a container window 31 for viewing thecontainer 14. The indicator window 30 may be a magnifying lens forproviding a clear view of the indicator arrangement 32. The indicatorarrangement 32 moves along with the needle actuator assembly 18 duringuse of the system 10 to indicate a pre-use status, use status, andpost-use status of the system 10. The indicator arrangement 32 providesvisual indicia regarding the status, although other suitable indicia,such an auditory or tactile, may be provided as an alternative oradditional indicia.

Referring to FIGS. 4-6, during a pre-use position of the system 10, thecontainer 14 is spaced from the drive assembly 12 and the valve assembly16 and the needle 28 is in a retracted position. During the initialactuation of the system 10, as shown in FIGS. 7-9, the drive assembly 12engages the container 14 to move the container 14 toward the valveassembly 16, which is configured to pierce a closure 36 of the container14 and place the medicament within the container 14 in fluidcommunication with the needle 28 via a tube (not shown) or othersuitable arrangement. The drive assembly 12 is configured to engage astopper 34 of the container 14, which will initially move the entirecontainer 14 into engagement with the valve assembly 16 due to theincompressibility of the fluid or medicament within the container 14.The initial actuation of the system 10 is caused by engagement of theactuation button 26 by a user, which releases the needle actuatorassembly 18 and the drive assembly 12 as discussed below in more detail.During the initial actuation, the needle 28 is still in the retractedposition and about to move to the extended position to inject the userof the system 10.

In the use position of the system 10, as shown in FIGS. 10-12, theneedle 28 is in the extended position at least partially outside of thehousing 20 with the drive assembly 12 moving the stopper 34 within thecontainer 14 to deliver the medicament from the container 14, throughthe needle 28, and to the user. In the use position, the valve assembly16 has already pierced a closure 36 of the container 14 to place thecontainer 14 in fluid communication with the needle 28, which alsoallows the drive assembly 12 to move the stopper 34 relative to thecontainer 14 since fluid is able to be dispensed from the container 14.At the post-use position of the system 10, shown in FIGS. 13-15A, theneedle 28 is in the retracted position and engaged with a pad 38 to sealthe needle 28 and prevent any residual flow of fluid or medicament fromthe container 14. The container 14 and valve assembly 16 may be thecontainer 14 and valve assembly 16 shown and described in InternationalPublication No. WO 2015/081337, which is hereby incorporated byreference in its entirety.

Referring to FIGS. 15A-15C, the pad 38 is biased into the pad as theneedle actuator body 96 moves from the use position to the post-useposition. In particular, the pad 38 is received by a pad arm 122 havinga cam surface 124 that cooperates with a cam track 126 on the bottomportion 24 of the housing 20. The pad arm 122 is connected to the needleactuator body 96 via a torsion bar 128. The cam surface 124 isconfigured to engage the cam track 126 to deflect the pad arm 122downwards thereby allowing the pad 38 to pass beneath the needle 28before being biased upwards into the needle 28. The torsion bar 128allows the pad arm 122 to twist about a pivot of the needle actuatorbody 96. The pad 38 may be press-fit into an opening of the pad arm 122,although other suitable arrangements for securing the pad 38 may beutilized.

Referring to FIGS. 1-33, the drive assembly 12 according to one aspectof the present invention is shown. As discussed above, the driveassembly 12 is configured to move the container 14 to pierce the closure36 of the container 14 and also to move the stopper 34 within thecontainer 14 to dispense fluid or medicament from the container 14.

For manufacturing purposes, using one size for a medicament container 14is often desirable, even if multiple fill volumes or dosages arecontemplated for use with the container 14. In such cases, whenmedicament containers are filled, the differing fill volumes result indifferent positions of the stopper 34. To accommodate such differentstopper 34 positions, as well as accommodate manufacturing differencesof the stoppers 34, aspects of the present invention include a bespokeor custom spacer or spacer assembly 40 disposed in a proximal end of thecontainer 14, proximal to the stopper 34. The custom spacer or spacerassembly 40 is selected from a plurality of different size spacers orspacer assemblies 40 to occupy space from a proximal end of the stopper34 to a proximal end of the container 14. In other words, the customspacer or spacer assembly 40 provides an option that allows dispensingof a range of manufacturer-set pre-defined fill volumes by selection ofdifferent spacers or spacer assemblies 40, and reduces or eliminates theneed for assembly configuration operations. The size of the customspacer or spacer assembly 40 can be employed to account for under-filledvolumes of the container 14, and provide a consistent bearing surface atthe proximal end of the container 14.

The drive assembly 12 shown in FIGS. 17-33 is configured to engage andcooperate with a spacer assembly 40 received by the stopper 34 of thecontainer 14. The spacer assembly 40 includes a spacer 42 and a spacerholder 44. The spacer holder 44 is received by the stopper 34 and thespacer 42 is received by the spacer holder 44. The spacer holder 44includes a first threaded portion 46 that engages a correspondingthreaded portion of the stopper 34, although other suitable arrangementsmay be utilized. The spacer 42 also includes a threaded portion 48 thatengages a corresponding second threaded portion 50 of the spacer holder44 for securing the spacer 42 to the spacer holder 44, although othersuitable arrangements may be utilized. The drive assembly 12 isconfigured to dispense a range of pre-determined fill volumes of thecontainer 14 while maintaining the functional features of the system 10described above, including, but not limited to, retraction of the needle28 after the end of the dose and providing an indication of the statusof the system 10 while also minimizing abrupt engagement of the stopper34 by the drive assembly 12. A discussed above, the drive assembly 12 isconfigured to dispense a plurality of discrete fill volume ranges byutilizing a plurality of sizes of the spacers 42. In one aspect, twelvefill volume ranges and twelve spacer 42 sizes are provided.

Referring to FIGS. 17-26, the drive assembly 12 includes a first plungermember 52, a second plunger member 54 received by the first plungermember 52, a first biasing member 56, a second biasing member 58, aplunger actuation member 60, and an index member 62. The first plungermember 52 is moveable from a pre-use position (shown in FIG. 18), to ause position (shown in FIG. 19), to a post-use position (shown in FIG.20) with the first plunger member 52 configured to engage the spacerassembly 40 and move the stopper 34 within the container 14 to dispensemedicament from the container 14. The first plunger member 52 isconfigured to move axially. The second plunger member 54 and the firstplunger member 52 form a telescoping arrangement with the second plunger54 configured to move axially after the first plunger member 52 moves apredetermined axial distance. The movement of the first and secondplunger members 52, 54 is provided by the first and second biasingmembers 56, 58, which are compression springs, although other suitablearrangements for the biasing members 56, 58 may be utilized.

The first biasing member 56 is received by the second plunger member 54and is constrained between the plunger actuation member 60 (and indexmember 62) and a first spring seat 64 of the second plunger member 54.The second biasing member 58 is positioned radially inward from thefirst biasing member 56 and received by the second plunger member 54.The second biasing member 58 is constrained between a second spring seat66 of the second plunger member 54 and the first plunger member 52. Thesecond biasing member 58 is configured to bias the first plunger 52member towards the container 14 from the pre-use position, to the useposition, and to the post-use position. The first biasing member 56 isconfigured to bias the second plunger member 54 towards the container14, which, in turn, biases the first plunger member 52 towards thecontainer 14 from the pre-use position, to the use position, and to thepost-use position. More specifically, the second biasing member 58 isconfigured to drive the first plunger member 52 against the spacerassembly 40 or stopper 34 to move the container 14 into engagement thevalve assembly 16 thereby piercing the closure 36 of the container 14and placing the container 14 in fluid communication with the needle 28.The first biasing member 56 is configured to move the stopper 34 withinthe container 14 to dispense the medicament within the container 14. Thesecond biasing member 58 has a different spring constant than the firstbiasing member 56. In particular, the second biasing 58 member isstiffer than the first biasing member 56 to provide a high force forpiercing the closure 36 of the container 14 while the first biasingmember 56 provides a lower force for dispensing as appropriate for theviscosity of the fluid or medicament within the container 14.

Referring again to FIGS. 17-26, the plunger actuation member 60 has anannular portion 68 and a spindle portion 70. The plunger actuationmember 60 is rotationally moveable relative to the first plunger member52 between a first rotational position and a second rotational positionspaced from the first rotational position. The first rotational positionmay be 15 degrees from the second rotational position, although othersuitable positions may be utilized. The annular portion 68 includes adrive surface 72 including a plurality of gears 74, although othersuitable arrangements may be utilized for the drive surface 72. Thespindle portion 70 includes an actuator locking surface 76 configuredfor engagement and release from a plunger locking surface 78 of thefirst plunger member 52. The plunger locking surface 78 includes aplurality of projections 80 configured to be received by a plurality ofslots or cutouts 81 defined by the actuator locking surface 76.

As shown in FIGS. 18 and 23, in the first rotational position of theplunger actuation member 60, the plurality of projections 80 and theplurality of slots or cutouts 81 are out of alignment such that theplunger actuation member 80 is engaged with the first plunger member 52to prevent movement of the first and second plunger members 52, 54 withthe first and second biasing members 56, 58 biasing the first and secondplunger members 52, 54 away from the plunger actuation member 60. Asshown in FIGS. 19 and 24, in the second rotational position of theplunger actuation member 60, the plurality of projections 80 and theplurality of slots or cutouts 81 are aligned with each other such thatthe plunger actuation member 60 is disengaged with the first plungermember 52 to allow movement of the first and second plunger members 52,54 thereby starting the dispensing process from the container 14.

Referring to FIGS. 7 and 33, the drive surface 72 of the plungeractuation member 60 is configured to be engaged by a portion of theneedle actuator assembly 18. After engagement of the actuator button 26and release of the needle actuator assembly 18, which is discussed inmore detail below, the needle actuator assembly 18 moves within thehousing 20 from the pre-use position, to the use position, and to thepost-use position. During the initial movement of the needle actuatorassembly 18, a portion of the needle actuator assembly 18 engages thedrive surface 72 of the plunger actuation member 60 to move the plungeractuation member 60 from the first rotational position to the secondrotational position. As shown in FIG. 33, an angled blade portion 82 ofthe needle actuator assembly 18 engages the drive surface 72 of theplunger actuation member 60 to cause rotation of the plunger actuationmember 60.

Referring to FIGS. 11, 13, and 26, the second plunger member 52 includesa plurality of coded projections 84 with a preselected one of theplurality of coded projections 84 configured to engage a restrictionmember 86 of the system 10. As discussed in more detail below, therestriction member 86 cooperates with the needle actuation assembly 18and restricts movement of the needle actuator assembly 18 from the useposition to the post-use position until a predetermined end-of-doseposition of the stopper 34 is reached. In one aspect, the restrictionmember 86 is configured to restrict axial movement of the needleactuation assembly 18 from the use position through engagement betweenthe restriction member 86 and a portion of the needle actuation assembly18. Such engagement between the restriction member 86 and the needleactuation assembly 18 is released by rotation of the restriction member86 when the stopper 34 reaches the end-of-dose position. During the useposition of the needle actuator assembly 18, the restriction member 86is biased in a rotational direction with the rotation of the restrictionmember 86 being prevented through engagement between the restrictionmember 86 and one of the plurality of coded projections 84 of the secondplunger member 54. The plurality of coded projections 84 may be axialribs of varying length, although other suitable arrangements may beutilized. Each coded projection 84 defines a point at which therestriction member 86 is able to rotate thereby releasing the needleactuator assembly 18. The smooth portion of the second plunger member 52may also provide a further “code” for determining when the system 10transitions to the end-of-dose position.

As discussed above, the indicator arrangement 32 moves with differentportions of the indicator arrangement 32 visible through the indicatorwindow 30 as the system 10 moves from the pre-use, use, and post-use orend-of-dose positions. More specifically, the indicator arrangement 32engages a portion of the restriction member 86 and moves along with therestriction member 86 through the various stages of the system 10 toprovide an indication to the user regarding the state of the system 10.

During assembly of the system 10, the dosage of the container 14 ismatched with a specific spacer 42 having a set length and acorresponding one of the plurality of coded projections 84 is alignedwith the restriction member 86. Accordingly, as discussed above, thecontainer 14 may be provided with a plurality of dosage volumes witheach volume corresponding to a specific spacer 42 and coded projection84. Thus, even for different dosage volumes, the system 10 is configuredto inject the needle 28 into the user to deliver a dose of medicamentfrom the container 14, retract the needle 28 after the end of the dose,and provide an indication of the status of the system 10 whileminimizing abrupt engagement of the stopper 34 by the drive assembly 12.In particular, the size of the stopper 34 may be selected to minimizethe distance between the first plunger member 52 and the spacer assembly40 and does not require the use of damping.

Referring to FIGS. 27-33, a drive assembly 12A according to a furtheraspect of the present invention is shown. The drive assembly 12A shownin FIGS. 27-33 is similar to and operates in the same manner as thedrive assembly 12 shown in FIGS. 17-26 and described above. In the driveassembly of FIGS. 27-33, however, the first plunger member 52 isreceived by the second plunger member 54 and extends from the secondplunger member 54 during axial movement from the pre-use position to theuse position. Further, the first plunger member 52 includes an extensionportion 88 configured to engage the second plunger member 54 after thefirst plunger member 52 moves predetermined axial distance such that thefirst and second plunger members 52, 54 move together. The first andsecond biasing members 56, 58 engage and act on the first and secondplunger members 52, 54 in the same manner as the drive assembly 12 ofFIGS. 17-26.

Referring to FIGS. 27-32, the index member 62 is positioned about thefirst and second plunger members 52, 54 and includes a plurality ofratchet teeth 90 configured to engage a flexible tab 92 positioned onthe bottom portion 24 of the housing 20. When the drive assembly 12, 12Ais installed into the bottom portion 24 of the housing 20, theengagement of the ratchet teeth 90 of the index member 62 with theflexible tab 92 of the housing 20 provide a one-way rotation of theindex member 62. The index member 62 is configured to rotate to alignone of the coded projections 84 of the second plunger member 52 with therestriction member 86 based on the dosage volume and spacer 42 size asdiscussed above. The index member 62 may provide the drive assembly 12,12A with 24 rotational positions of which 12 may have unique dose valuesassociated with them.

Referring to FIGS. 1-16 and 34-40B, the needle actuator assembly 18according to one aspect of the present invention is shown. The needleactuator assembly 18 includes a needle actuator body 96 having guidesurfaces 98, a needle shuttle 102 having cam surfaces 104, and theneedle 28 received by the needle shuttle 102 and configured to be influid communication with the container 14 as discussed above. The needleactuator body 96 is generally rectangular with the guide surfaces 98protruding radially inward. The needle shuttle 102 is received withinthe needle actuator body 96. As described above, the needle actuatorbody 96 is moveable within the housing 20 from a pre-use position (shownin FIGS. 4-6), an initial actuation position (FIGS. 7-9), a use position(FIGS. 10-12), and a post-use position (FIGS. 13-15A). The needleactuator body 96 is biased from the pre-use position to the post-useposition via an extension spring 106, although other suitable biasingarrangements may be utilized. The needle actuator body 96 is releasedand free to move from the pre-use position to the use position uponengagement of the actuator button 26, which is discussed in more detailbelow. The needle actuator body 96 moves from the use position to thepost-use position after rotation of the restriction member 86 asdiscussed above in connection with FIGS. 17-33.

Referring to FIGS. 34-40B, the needle shuttle 102 is moveable along avertical axis between a retracted position where the needle 28 ispositioned within the housing 20 and an extended position where at leasta portion of the needle 28 extends out of the housing 20. The needleshuttle 102 is configured to move between the retracted position and theextended position through engagement between the guide surfaces 98 ofthe needle actuator 96 and the cam surfaces 104 of the needle shuttle102. The cam surfaces 104 are provided by first and second cam members108, 110, with the first cam member 108 spaced from the second cammember 110. The housing 20 includes a guide post 112 having recessconfigured to receive a T-shaped projection 114 on the needle shuttle102, although other shapes and configurations may be utilized for theguide post 112 and T-shaped projection 114. The needle shuttle 102 movesalong the guide post 112 between the retracted and extended positions.The guide post 112 is linear and extends about perpendicular from thehousing 20, although other suitable arrangements may be utilized. Theguide surfaces 98 of the needle actuator body 86 are non-linear and eachinclude a first side 116 and a second side 118 positioned opposite fromthe first side 116.

As discussed below, the guide surfaces 98 of the needle actuator body 96cooperate with the cam members 108, 110 of the needle shuttle 102 tomove the needle shuttle 102 vertically between the retracted andextended positions as the needle actuator body 96 moves axially from thepre-use position to the post-use position. The needle shuttle 102 alsoincludes a shuttle biasing member 120 configured to engage the housing20 or the actuator button 26. In particular, the shuttle biasing member120 engages the housing 20 or actuator button 26 and provides a biasingforce when the needle actuator body 96 is transitioning from the useposition to the post-use position. When the needle actuator body 96 isfully transitioned to the post-use position, the cam members 108, 110 ofthe needle shuttle 102 are disengaged from the guide surfaces 98 of theneedle actuator body 96 and the shuttle biasing member 120 biases theneedle shuttle 102 downward such that the needle 28 engages the pad 38,as discussed above. As discussed above in connection with FIGS. 1-16,however, the pad 38 may also be biased into the needle 28 rather thanbiasing the needle shuttle 102 downwards via the shuttle biasing member120. The needle actuator body 96 may interact with the actuator button26 to prevent the actuator button 26 from popping back up until thepost-use position is reached, which is discussed below in more detail.

Referring to FIGS. 37A-40B, in a pre-use position (FIG. 37A), the needleshuttle 102 is in the retracted position with the cam members 108, 110spaced from the guide surface 98 of the needle actuator body 96. As theneedle actuator body 96 moves to the use position (FIGS. 37B and 38A),the second cam member 110 of the needle shuttle 102 engages the secondside 118 of the guide surfaces 98 to move the needle shuttle 102 fromthe retracted position to the extended position. During the transitionfrom the use position to the post-use position of the needle actuatorbody 96 (FIG. 37C), the first cam member 108 of the needle shuttle 102is engaged with the first side 116 of the guide surfaces 98 to move theneedle shuttle 102 from the second position to the first position. Afterthe needle actuator body 96 is fully transitioned to the post-useposition (FIGS. 37D and 38B), the shuttle biasing member 120 biases theneedle shuttle 102 downward as the cam members 108, 110 disengage fromthe guide surfaces 98 of the needle actuator body 96 with the needle 28engaging the pad 38. The transition of the needle actuator body 96 andthe corresponding position of the needle shuttle 102 is also shown inFIGS. 39-40B. The interaction between the actuator button 26 and theneedle actuator body 96 is discussed in detail in connection with FIGS.65A-67. Referring to FIGS. 41-64, a drug delivery system 200 accordingto a further embodiment is shown. The system 200 includes a housing 202having an upper housing 204 and a lower housing 206. The housing has aproximal end 205 and a distal end 207. The upper housing 204 has astatus view port 208 so that a user can view the operating status of thesystem 200. The system 200 also includes a valve assembly 212, a tube214 fluidly connecting the valve assembly 214 with a patient needle 215that is disposed in a proximal end of a needle arm 216. A spring 218biases a needle actuator 220 distally.

As shown in FIGS. 42-46, the system 200 additionally includes acontainer or medicament container 222 with a stopper 224 movablydisposed therein, although the stopper 224 is omitted from variousfigures to aid clarity. Preferably, the distal end of the medicamentcontainer 222 has a septum assembly 228 that is spaced apart from thevalve assembly 212 prior to actuation of the device 222, as best shownin FIG. 47.

As shown in FIGS. 45-47, the spacer 226 is selected from a plurality ofdifferent size spacers 226 to occupy space from a proximal end of thestopper 224 to a proximal end of the container 222. The spacer 226 issubstantially flush with the proximal end of the container 222.Additionally, the spacer 226 has a “top hat” shape, which includes acentral column 230 and a distal flange 232, as best shown in FIG. 45.

Returning to FIGS. 44-47, the system 200 also includes a drive assembly234 for displacing the container 222 distally to establish the fluidconnection between the container 222 and the patient needle 215, as wellas dispensing the medicament from the container 222. In more detail, thedrive assembly 234 includes an inner spring 236 disposed within acentral plunger 238, an outer plunger 240, an outer spring 242 disposedbetween the central plunger 238 and the outer plunger 240, a telescopingmember 244, and a release gate 246.

Preferably, the inner spring 236 has a greater spring constant than theouter spring 242, and is therefore, stronger or stiffer than the outerspring 242. The inner spring 236 is disposed inside the central plunger238, and pushes between a spring flange 248 in the lower housing (bestshown in FIG. 46) and the central plunger 238, which bears directly onthe proximal end of the spacer 226 subsequent to device activation. Theouter spring 242 is disposed inside outer plunger 240, and pushesbetween a proximal external flange 250 of the central plunger 238 and adistal internal flange 252 of the outer plunger 240. Thus, the inner andouter springs 236 and 242 are nested, and can provide a more compactdrive assembly (and thus, a more compact system 200) than employing asingle spring.

According to one aspect, the inner spring 236 acts only to displace thecontainer 222 to establish the fluid connection with the patient needle215, and the outer spring 242 acts only to subsequently dispense themedicament from the container 222. According to another aspect, theinner spring 236 acts to displace the container 222 to establish thefluid connection with the patient needle 215, and also acts to begindispensing the medicament from the container 222, and the outer spring242 acts to complete dispensing the medicament. In a further aspect, theinner spring 236 causes the initial piercing of the container 222 withthe outer spring 242 completing the piercing and dispensing of themedicament from the container 222.

As shown in FIGS. 44-47, and as subsequently described in greaterdetail, the outer plunger 240 includes a pair of proximal flanges orfeet 254 that each have a slanted surface that interacts with acorresponding slanted surface (or surfaces) on the release gate toretain and subsequently release the power module subsequent to actuationof the device 200.

As best shown in FIGS. 46 and 47, as initially assembled, the container222 is disposed in clearance from the drive assembly 234 and the valveassembly 212. A lateral flange 256 on the needle actuator 220 axiallyretains the medicament container 222, and the needle actuator 220prevents the release gate 246 from displacing laterally. According toone embodiment, a spring (not shown) biases the needle actuator 220distally, but the actuation button 210 (and/or its associated assembly)prevents distal displacement of the needle actuator 220 prior toactuation of the device 200. A status bar 258 is disposed on the needleactuator 220, and has a top surface that is visible through the statusview port 208. According to one embodiment, the top surface of thestatus bar has a plurality of colors or patterns, and when the device isin a pre-actuated state, a first color or pattern, such as yellow, isvisible through the status view port 208.

FIGS. 48-52 are top views of the system 200 illustrating the operationof events at and subsequent to actuation of the system 200. In FIG. 47,a user slides the actuation button 210 proximally and then displaces thebutton 210 vertically into the housing 202, thereby freeing the needleactuator 220 to displace distally under the influence of the spring(omitted for clarity). As shown in FIG. 49, as the needle actuatordisplaces distally, tracks 260 on the needle actuator 220 interact withlateral bosses 262 on the needle arm 216 to insert the patient needle215. Preferably at this stage, the proximal end of the needle actuator220 has not yet cleared the release gate 246, and thus, the driveassembly 234 has not yet been released. But the lateral flange 256 hasdisplaced distally and therefore, the container 222 is unrestrained.

Subsequently, as shown in FIGS. 50 and 51, with continued distaldisplacement, the proximal end of the needle actuator 220 clears therelease gate 246 (thereby releasing the drive assembly 234). The needleactuator 220 comes to temporarily rest against a feature on a rotatablerelease flipper 264, driving the release flipper 264 against anoutrigger 266 (best shown in FIGS. 44 and 59) of the telescoping member244. The needle actuator 220 remains in this position until themedicament has been dispensed. In this position, preferably, a secondcolor or pattern of the status bar 258, such as green, is visiblethrough the status view port 208.

At this stage, the force of the springs 236 and 242 and the interactionof the angled surfaces of the proximal flanges or feet 254 with thecorresponding angled surface (or surfaces) on the release gate 246causes the release gate 246 to displace laterally, thereby freeing theouter plunger 240 from restraining interaction with the release gate246. Up to this point, the outer plunger 240 has been restraining thecentral plunger 238.

Referring to FIGS. 52 and 53 (the inner spring 236 is omitted from FIG.52 for clarity), the stiff inner spring 236 distally drives centralplunger 238 to contact the spacer 226. Because the medicament container222 is filled with a substantially incompressible fluid, the continueddistal displacement of the central plunger 238 distally displaces thespacer 226, the stopper 224, and the container 222 relative to thehousing 202. This distal displacement causes the septum assembly 228 tobe pierced by the valve assembly 212, establishing fluid communicationbetween the container 222 and the patient needle 215. The centralplunger 238 travels distally until its proximal external flange 250(best shown in FIG. 59) contacts a flange on the lower housing 206,thereby limiting the “piercing travel.” Preferably, another flange onthe lower housing 206 and/or the lateral flange 256 of the needleactuator 220 limits distal travel of the container 222.

Subsequently, because the inner spring 236 can no longer distallydisplace the central plunger 238, the lighter outer spring 242 distallydisplaces the outer plunger 240 relative to the central plunger 238 tocontact the distal flange 232 of the spacer 226, as shown in FIGS. 54and 55. As subsequently described in greater detail, preferably, thecontact between the outer plunger 240 and the spacer 226 is damped tominimize the impact force. Further expansion of the outer spring 242distally displaces the outer plunger 240 to dispense the medicament.

As shown in FIGS. 56 and 57, as the outer spring 242 continues to expandand distally displace the outer plunger 240, upon a predetermined distaldisplacement of the outer plunger 240 relative to the telescoping member244, an external feature or flange 268 of the outer plunger 240interacts with an internal distal feature or flange 270 of thetelescoping member 244 to “pick up” the telescoping member 244. Thisensures that further distal displacement of the outer plunger 240 causescorresponding distal displacement of the telescoping member 244. Thispaired distal displacement continues until the end of the medicamentdispensing.

As previously noted, the outrigger 266 is disposed on the telescopingmember 244. The axial length of the outrigger and the distal travel ofthe telescoping member 144 controls the timing of the disengagement ofthe outrigger 266 with the release flipper 264. As shown in FIGS. 58 and59, at the end of medicament dispensing, the proximal end of theoutrigger 266 bypasses the release flipper 264. This allows the releaseflipper 264 to rotate out of engagement with the needle actuator 220(FIG. 60), and allows the needle actuator 220 to continue its distaldisplacement and withdraw the patient needle 215 (FIG. 61). At thisstage, another color or pattern of the status bar 258, such as red, isvisible through the status view port 208, signifying that the device 200has completed operation.

As previously noted, the contact between the outer plunger 240 and thespacer 226, as illustrated in FIGS. 62 and 63, is preferably damped tominimize the impact force. The highest level of energy dissipation isdesirable for under-filled syringes containing viscous fluid, as theouter spring 242 will be stiffer to provide desired dispense rates. Thelowest level of energy dissipation is desirable for maximum-filledsyringes containing low-viscosity fluid, as the outer spring can be lessstiff to provide desired dispense rates. Various methods can be employedto adjust damping levels, such as air damping, or closed-cell foamdamping.

As another method of damping the impact force, FIG. 64 illustrates anembodiment of a spacer 226 in which one or more axial interface ribs 272are circumferentially arrayed about the central column 230 of the spacer226. In this embodiment, the outer plunger 240 must drive past theinterference ribs 272, which provide frictional resistance to the distaldisplacement of the outer plunger 240 relative to the spacer 226. Thefrictional force created by the interference between interference ribs272 and the outer plunger 240 is independent of plunger speed.Preferably, the frictional force does not exceed the minimum dispensespring load, to avoid stalling weaker springs. The interference can betuned to give the desired level of frictional resistance. For differentfluid viscosities, there can be different sizing (axial and/or radial)of the interference ribs 272. This could mean a bespoke or custom spacerfor each viscosity and fill-level combination, or, depending on thenumber of springs required for a viscosity range, there can be a numberof tined positions, whereby the spacer can be set to a particularposition for a particular modular spring (the position have had theinterference/damping tuned for that particular spring load/viscosityscenario).

Referring to FIGS. 65A-69, an actuator button arrangement 280 foractuating the system 10 according to one aspect of the present inventionis shown. The actuator button arrangement 280 includes the actuatorbutton 26, a button spring 284, and a needle actuator body 286. Theneedle actuator body 286 may be similar to the needle actuator bodies96, 220 discussed above and configured to move within the housing 20 totransition the needle shuttle 102 or needle 28 between retracted andextended positions. As shown in FIG. 69, the actuator button 26 includesa user interface portion 288 for interacting with a user. Preferably,the user interface portion 288 is about 22 mm long and about 10 mm wide,although other suitable dimensions may be utilized. The actuator button26 includes two pairs of lockout arms 290, 292 that interact with buttoncontacting surfaces 294, 296 on the needle actuator body 286 prior todevice actuation to prevent the needle actuator body 286 from rockingupward. As shown in FIG. 65H, an overlap between the needle actuatorbody 286 and the housing 20 prevents premature actuation. Referring toFIG. 66, the button spring 284 includes a first bearing surface 298 anda second bearing surface 300 spaced from the first bearing surface 298,and a cantilevered central spring arm 302 surrounded by a pair of outerarms 304 that are joined by the first bearing surface 298.

The actuation button arrangement 280 is configured to provide one ormore of the following features, which are discussed in more detailbelow: one-way axial displacement or sliding of the actuator button 26;transverse movement (raised and depressed positions) of the actuatorbutton 26 where the actuator button 26 remains depressed during the useposition of the needle actuator body 286; and lockout of the actuatorbutton 26 in the post-use position of the needle actuator body 286 suchthat the button 26 is in the raised position and cannot be depressed bya user.

To actuate the system 10 using the actuator button 26, the user firstslides the user interface portion 288 in a first axial direction, shownas being to the right in FIGS. 65G and 65H. The user may be required toslide the user interface portion 288 about 10 mm or about 8 mm, althoughother suitable distances may be utilized. Moving the actuator button 26axially moves the lockout arms 290, 292 to clear the button contactsurfaces 294, 296 on the needle actuator body 286 to allow movement ofthe actuator button 26 from the raised position to the depressedposition.

As the user distally slides the user interface portion 288, the centralspring arm 302 of the button spring 284 rides over a spring arm 306bearing surface on the housing 20 while the first and second bearingsurfaces 298, 300 engage first and second bearing ramps 308, 310 on thehousing 20. The forces on the button spring 284 are balanced through theengagement with the spring arm bearing surface 306 and the first andsecond bearing ramps 308, 310 to provide a smooth axial displacement orsliding of the actuator button 26.

As the actuator button 26 and the button spring 284 reach the end oftheir axial sliding travel, the central spring arm 302 and the firstbearing surface 298 pass the end of a respective stops 312, 314 toprevent the actuator button 26 from sliding backward to its originalposition, as shown in FIG. 65H. Further, when the actuator button 26 andthe button spring 284 reach the end of their axial sliding travel, theuser engages the user interface portion 288 to move the actuator button26 downward to its depressed position. The actuator button 26 may bedepressed about 2 mm and the minimum force required to depress theactuator button 26 is about 3 N, and most preferably, about 2.8 N,although other suitable distances and minimum forces may be utilized.

As the user depresses the user interface portion 288, shown in FIGS. 65Aand 65B, the actuator button 26 rotates the needle actuator body 286 torelease the needle actuator body 286 thereby allowing the needleactuator body 286 to move from the pre-use position to the use position.As shown in FIG. 65B, as the needle actuator body 286 travels to the useposition, the lockout arms 290, 292 run along the underside of thebutton contact surfaces 294, 296 to prevent the actuator button 26springing upward. After the medicament has been delivered and as theneedle actuator body 286 is transitioning from the use position to thepost-use position, shown in FIG. 65C, the lockout arms 290, 292 aredisengaged from the button contact surfaces 294, 296 allowing theactuator button 26 to spring back up under the influence of the buttonspring 284. Once the needle actuator body 286 fully transitions to thepost-use position, shown in FIG. 65D, the actuator button 26 hasfinished moving from the depressed position to the raised position dueto the biasing force of the button spring 284. When the needle actuatorbody 286 is in the post-use position, a spring arm 316 on the needleactuator body 286 engages the actuator button 26 to prevent the actuatorbutton 26 from moving to the depressed position while axial movement isstill restricted by the engagement of the spring arm 302 with the stops312, 314. Thus, the actuator button 26 is locked after delivery of themedicament is complete to provide a clear indication between a usedsystem and an unused system.

Furthermore, if the user holds down the actuator button 26 duringdispensing of the medicament, proper dosing and needle retraction willstill complete, but the actuator button 26 will not spring back up tothe raised position until the button 26 is released.

In one aspect, the button spring 284 is made of plastic. The buttonspring 284 may also be a pressed metal spring could be used instead,although any other suitable material may be utilized.

Referring to FIGS. 68A-68G, rather than providing a separate actuatorbutton 26 and button spring 284, the spring may be provided integrallywith the button 26. More specifically, an actuator button 320 accordingto a further aspect of the present invention includes an integral springarm 322. The actuator button 320 also includes lockout arms 324,retention arms 326, and a rear pivot 328. As shown in FIGS. 68D and 68E,the spring arm 322 engages prongs 330 in the top portion 22 of thehousing 20. During transition of the system 10 from the pre-use positionto the use position, the spring arm 322 slides past a detent of theprongs 330 providing an axial spring force. The end of the spring arm322 engages a portion of the top portion 22 of the housing 20 to providethe vertical spring force as the spring arm 322 deflects. The actuatorbutton 320 is configured to a fluid motion between the sliding anddepression movements of the button 320 even though two separate motionsare occurring, which is similar to the operation of the button 26discussed above. During transition between the pre-use position and theuse position, the button 320 pivots about the rear pivot 328 with theretention arm 326 engaging a portion of the needle actuator body 286thereby maintaining a depressed position of the button 320 until theend-of-dose position is reached in a similar manner as actuator button26. The lockout arms 324 deflect inwards and engages a portion of theneedle actuator body 286 as the needle actuator body 286 moves to theend-of-dose position thereby preventing further movement of the actuatorbutton 320 in a similar manner as the actuator button 26 discussedabove.

Aspects of the present invention provide improvements over previousbutton designs. For example, the actuation button arrangement 280provides multiple surfaces to hold the needle actuator body 286 in placeagainst a needle actuator spring 106 prior to actuation, therebyreducing the likelihood of premature actuation during a drop impact. Theactuation button arrangement 280 physically prevents the needle actuatorbody 286 from moving prior to actuation by holding it in a tilted(locked) state in such a way that the surfaces have no room to separateand pre-activate.

In addition, button slide forces of the actuation button arrangement 280are controlled more precisely by utilizing a flexing arm rather thanusing a simple bump detent. This permits longer sliding strokes of thebutton 26 with better force control, resulting in a more ergonomicallyeffective design. Further, the actuation button arrangement 280 causesthe button 26 to pop back out at the end of injection, giving the useran additional visual, audible, and tactile indication that themedicament delivery is completed.

According to one aspect, the fluid delivery volume of the system 10 isdetermined by the end position of a plunger relative to a point insidethe housing regardless of actual fill volume, container inner diameter,and stopper starting position and length. The dosing accuracyvariability can be significant because the tolerances of the factorsabove can be quite large. Aspects of the present invention allow for theelimination of some or all of these tolerances from the dosing equation,resulting in a more precise and less variable injection volume ofmedicament.

Referring to FIGS. 69 and 70, a restriction member 452 according to oneaspect of the present invention is disposed with the drive assembly. Therestriction member 452 governs the timing of the final displacement ofthe needle actuator bodies 96, 220 subsequent to the completion of themedicament dose. Instead of rotating about a fixed post, the restrictionmember 452 floats freely. Once a plunger displaces sufficiently distallyfor a gap to align with the restriction member 452 (as shown in FIGS. 70and 71), the restriction member 452 displaces laterally into the gapbecause of the force of the spring on the needle actuator 96, 220 andthe angled face 454 on the rear of the arm of the restriction member 174that engages the needle actuator body (best shown in FIG. 71). Once therestriction member no longer retains the needle actuator body 96, 220,the needle actuator body 96, 220 is free to complete the axial movementto the post-use position. Further, as shown in FIG. 71, the restrictionmember 452 is biased onto the rear of the barrel portion of thecontainer 14, which minimizes the tolerance chain of the variouscomponents and improves dose accuracy.

Referring to FIGS. 72-77, a drive assembly 500 for a drug deliverysystem according to one aspect of the present invention is shown. Thedrive assembly 500 includes an actuation button 506, a container 508, aneedle actuator assembly 510, an actuation release or flipper 512, alead screw 514, and a plunger 516. The lead screw includes a drumportion 518 with external radially-protruding vanes 520, and, as bestshown in FIGS. 74 and 75 and subsequently described in greater detail, ascrew thread portion 522. Prior to activation, as best shown in FIGS. 73and 76 one end 513 of the actuation release 512 engages one of the vanes520 to prevent rotation of the lead screw 514.

According to one aspect, as shown in FIGS. 74-76, the screw threadportion 522 of the lead screw 514 engages internal threads of a nut 524connected with the plunger 516. According to another aspect, the nut andits internal threads are integrally formed with the plunger as a unitarystructure. Additionally, a constant force spring 526 is received withinthe drum portion 518 and biases the lead screw 514 in a rotationaldirection. According to one aspect, the spring 526 is secured to thebase cover 504. According to another aspect, as shown in FIGS. 74-76, adrive assembly housing 528 is disposed within the system and the spring526 is secured to the power pack housing 528.

Unlike a helical spring, such as a compression spring, which has a forceprofile proportional to its displacement, the constant force spring 526and the like maintain a relatively flat or even force profile over along working length. The even force profile advantageously provides aninjection force that is proportional to the spring force. This willprovide a flat or even injection force, and thus, a substantiallyconstant injection rate for the medicament. Although the spring 526 isillustrated in FIG. 76 as having only two turns of material, one skilledin the art will appreciate that fewer or greater numbers of turns can beemployed. Preferably, an assembler winds the spring 526 when the driveassembly 500 is assembled, and the spring 526 is stored in the woundposition until the time of actuation.

Upon actuation of the system, the needle actuator assembly 510 isreleased to axially displace (to the right in FIGS. 72-75) from thepre-use position to the post-use position under the influence of abiasing member 530 (best shown in FIG. 732). During this displacement,the needle actuator assembly 510 bears against a second end 532 of theactuation release 512 and rotates the release 512 counter-clockwise, asshown in FIG. 77. This counter-clockwise rotation of the actuationrelease 512 frees the first end 513 thereof from engagement with thevane 520. Subsequent to the disengagement of the first end 513 from thevane 520, the spring 526 unwinds and drives rotation of the lead screw514, which, in combination with the nut 524, advances the plunger 514 todispense the medicament.

As the lead screw 514 is rotating, the rotation of the drum portion 518and the vanes 520 is visible through a window 534 in the housing. Thiswindow 534 indicates progress of the screw in a way that is much moreapparent than viewing the linear movement of the stopper 536 in thecontainer 508. In fact, this rotational movement is many times moresensitive than the linear movement. One skilled in the art willappreciate that the exact amount of advantage or increase depends on thepitch of screw thread portion 522 of the lead screw 514, the diameter ofthe drum portion 518, and number of vanes 520 on the drum portion 518.

Referring to FIGS. 78-83, a drive assembly 600 for a drug deliverysystem according to a further aspect of the present invention is shown.The drive assembly 600 acts to store a spring's mechanical energy and toactivate it when triggered. The drive assembly 600 includes a medicamentbarrel 601, a stopper 602 slidably disposed in the barrel 601, a firstvalve plunger 603, a second valve plunger 604, a first revolve nut 605,and a second revolve nut 606. The drive assembly 600 also includes arotary indicator 607, a locking element 608, a constant force spring 609disposed within the rotary indicator 607, and an actuation release orflipper 610. The drive assembly 600 is at least partially disposedwithin a housing 611 that can be assembled into a drug delivery system.

The constant force spring 609 is contained between the housing 611 andthe rotary indicator 607 within a drum portion 616 of the rotaryindicator 607. The drive assembly's inactive state is such that energyis applied by uncoiling the spring 609 and harnessing this energygeometrically with the housing 611, rotary indicator 607, and actuationrelease 610. When the drive assembly 600 is deactivated, the springrecoils and translates the mechanical energy into rotational motion ofthe rotary indicator.

The telescoping multi-part plunger is oriented along a force axisbetween the medicament barrel 601 and the rotary indicator 607. Therotary indicator 607 features a threaded shaft 618. According to oneaspect, the threads are dual lead, and are either square or rectangularin nature. The multi-part telescoping plunger includes a two-partthreaded nut (first revolve nut 605 and second revolve nut 606) and atwo-part plunger (first valve plunger 603 and second valve plunger 604).The second revolve nut 606 is a threaded shaft that mates with therotary indicator 607 and first revolve nut 605 and features matchingthreads on its inner and outer surfaces (internal and external threads,respectively) to mate with them. The second revolve nut 606 also has acircular collar 620 (best shown in FIG. 82) on its proximal end thatbottoms down on the second valve plunger 604. The second revolve nut 606is free to spin along the force axis. The first revolve nut 605 is alsoa threaded shaft that features threads on its inner diametercorresponding to the external threads of the second revolve nut 606 tomate with the second revolve nut 606.

According to one aspect, on one end, the first revolve nut 605 has ahexagonal collar that press fits on the first valve plunger 603 tofixedly connect the first valve plunger 603 with the first revolve nut605. In the drive assembly 600, the first revolve nut is not free torotate and will only translate when the power module subassembly isactuated.

The second valve plunger 604 is a hollow cylindrical component with asmall collar 622 on its distal end, a large collar 624 on its proximalend, and an extended L-shaped arm 626 (best shown in FIG. 83) protrudingfrom the large proximal collar 624. According to one embodiment, thesmall collar 622 is discontinuous and features four leaf cantileveredarms or leaf springs 623 that allow the collar to bend and mate with thefirst valve plunger 603. The inner surface of the second valve plunger604 has an undercut through its length terminating at its proximal end aradially inward protruding shelf 628 of the large collar 624. The shelf628 engages the second revolve nut 606 within the telescoping assembly.

The first valve plunger 603 attaches to the stopper 602 and is also ahollow cylindrical component that mates with the second valve plunger604. More specifically, the first valve plunger 603 features acylindrical protrusion 630 on its distal end to mate with the stopper602. According to one aspect, as best shown in FIG. 79, four thru slots632 are disposed on the proximal quadrants of the first valve plunger603 to mate with the leaf springs or arms 623 and small collar portion622 of the second valve plunger 604. Both the first and second valveplungers 603 and 604 are free to slide.

Telescoping is achieved when the constant force spring 609 recoils andthe rotary indicator 607 starts spinning. The threaded attachmentbetween the rotary indicator 607 and the second revolve nut 606 causessecond revolve nut 606 to rotate. But because the second revolve nut 606is threaded to the first revolve nut 605, which cannot rotate andexperiences resistance to distal translation due to the pressure causedby medicament in the barrel 601, the second revolve nut 606 willdisplace proximally and bottom out on the second valve plunger'sradially inward protruding shelf 628. The second valve plunger 604 isprevented from displacing proximally by the housing 611. Subsequently,and with continued rotation of the rotary indicator 607, because thesecond revolve nut 606 is threaded with the first revolve nut 605 (whichcannot rotate) the first revolve nut 605 translates distally to push thefirst valve plunger 603 (and the stopper 602) to dispense medicamentfrom the barrel 601.

The first valve plunger 603 displaces distally relative to the secondvalve plunger 604 until the small collar sections 622 (respectivelydisposed on the distal ends of the leaf springs or arms 623 of thesecond valve plunger 604) engage the corresponding proximal ends of theslots 632 of the first valve plunger 603. This locks the relativepositon of the first and second valve plungers 603 and 604, withcontinued rotation of the rotary indicator 607, both valve plungerstranslate distally while also pushing the second revolve nut along(because of its proximal engagement with the shelf 624).

The initial and final positions of the telescoping plunger, and thus themedicament dose, are controlled by the rectangular thread form of thethreaded shaft 618 of the rotary indicator 607, a threaded shaft on thedrum portion 616 of the rotary indicator 607, and a stepped pin thatacts as the locking element 608. According to one aspect, threaded shafton the drum portion 616 of the rotary indicator 607 is single lead, andbecause the rest of the components in the telescoping chain have duallead threads, the axial travel of the other threaded components is twicethe axial travel of the lock 608 relative to the rotary indicator.

According to one embodiment, the lock 608 is cylindrical and features adomed tip on one end and a cylindrical collar on the other. The threadson the exterior of the rotary indicator's drum portion 616 along with aslot and undercut 636 at the bottom of the housing 611 captures the lock608 in place, allowing it to slide parallel to the force axis. Thus, asthe spring 609 is released and the rotary indicator 607 turns, the lock608 translates as well and creates a positive stop when the distal endof the thread on the exterior of the rotary indicator's drum portion 616is reached.

One benefit of aspects of the drive assembly 600 include the use of aconstant force spring 609, the mechanical energy of which is convertedinto substantially constant linear force to the medicament in the barrel601. In turn, this creates a uniform medicament delivery rate. Anotherbenefit is that employing the telescoping plunger driven by a threadform, the drive assembly can create in-line space savings of up to 0.75inches compared to other plunger designs. Additionally, the driveassembly provides a controlled medicament dose through an initial andfinal mechanical constraint within the same component.

As previously noted, other drug delivery systems utilize a compressedcoil spring, which exerts a maximum force at actuation that eventuallydecreases as the spring expands. A decreasing force at the plungertranslates into variable medicament delivery time and medicament exitpressure. By using a constant force spring, the force exerted on theplunger is constant from the beginning to the end of the dosage. Inaddition, the distance a coil spring has to travel in addition to thelength of a static plunger that needs translate inside the drugcontainer can create a long assembly. In contrast, in embodiments of thepresent invention, the constant force spring is contained radially anddoes not require any additional space before or after activation.Furthermore, the aspects of the telescoping plunger allow that theplunger length of the can be significantly reduced in comparison to thelength of a static plunger.

Previous drug delivery systems have variable dose accuracy performancebecause the mechanical components enabling the drug delivery create ageometric dependence by bottoming down on the container, which cannot befabricated with tight tolerances. Some embodiments of the presentinvention create a control to the start and end times of the translatingplunger via a thread form in the rotary indicator and the use of theconstant force spring.

The drive assembly creates a space saving geometry in addition towell-controlled time, volume and pressure for the drug delivery device,which translates to a more attractively compact and precise drugdelivery device.

Some aspects of the drive assembly implement three rotating threadedshafts to create a linear space savings of about 0.75 inch. In otheraspects, the same concept can be employed using two rotating threadedshafts and result in a space savings of about 0.5 inch. Some aspects ofthe present invention convert the rotational energy of a constant forcespring to a translational force motion of a plunger.

Referring to FIGS. 84A-84G, a plunger assembly 400 for use in connectionwith a drive assembly according to one aspect of the present inventionis shown.

Elements in a chain of tolerances in the plunger assembly 400 include athickness (A) of a flange 402 of an inner plunger 404, an internallength (B) of an outer plunger 406 between an internal proximal end 408and an internal shoulder 410, and an initial offset distance (C₁)between the inner plunger flange 402 and the internal proximal end 408of the outer plunger. This initial offset distance (C₁) is preferablygreater than a gap distance (C₂) between outer plunger 406 and theproximal end of the medicament barrel 412. The chain of tolerances inthe stopper spacer assembly 400 also includes the internal barreldiameter (D). Once assembled, the stopper spacer 414 and the outerplunger 406 are unique for a given medicament volume.

FIGS. 84B-84G illustrate operation of the plunger assembly 400. As shownin FIG. 84B, when the system is actuated, the both inner and outerplungers 404 and 406 are released. An outer spring 416 pushes the outerplunger 406 into the barrel 412, compressing damping material 418, andan inner spring 420. The stopper 422 does not yet moved relative to thebarrel 412 due to the fluid column of medicament.

Next, as shown in FIG. 84C, the outer spring 416 distally displaces theouter plunger 406 and the barrel 412 to open a valve (not shown) at thedistal end of the barrel 412 that establishes fluid communication withthe needle (not shown). Due to the incompressibility of the liquidmedicament, the stopper 422 cannot displace relative to the barrel 412until the valve is opened and the fluid path to the patient needle isestablished.

Subsequently, as shown in FIGS. 84D and 84E, the inner spring 420displaces the inner plunger 404, the stopper spacer 414, and the stopper422, to dispense the fluid.

FIG. 84F illustrates the end of medicament delivery when the proximalflange 402 of the inner plunger 404 contacts the internal shoulder 410of the outer plunger 406, thereby ceasing displacement of the innerplunger 404 (and the stopper spacer 414 and stopper 422) relative to themedicament barrel 212 and stopping the flow of medicament.

According to one aspect, as shown in FIG. 84G, the cessation ofdisplacement of the inner plunger 404 relative to the medicament barrel412 triggers an end-of-dose indicator for the system.

While a specific spacer assembly 40 and spacer 226 have been describedabove, the custom spacer assembly may have a variety of configurations.The custom spacer assembly may be situated against a proximal end of thestopper in the container or connected to the stopper in another manner.The spacer design is such that its effective length can be changed inorder to allow the dispensing of a precise quantity of medicament. Thelength adjustment is intended to compensate for manufacturing toleranceswithin the container, the fill volume, and especially the stopperlength, which can add up to ⅓ of the variability in a delivered doseusing a non-adjustable spacer. The spacer length can be adjusted throughseveral techniques, depending on the specific aspect. The spacer lengthcan be self-adjusting based on its location to the back of thecontainer, adjustable by assembly equipment at the time of finalassembly of the primary container into the subassembly, and it can bemade an integral part of the stopper and adjusted as a subassembly priorto filling. The adjustable spacer allows a more precise volume of fluidto be injected compared to a non-adjustable stopper.

Referring to FIGS. 85 and 86, a collapsible spacer assembly 430 includesa forward spacer portion 432 secured to a stopper 434, an inner plunger436, a rear spacer portion 438, and a rotating shuttle 440. The innerplunger 436 can translate relative to the forward spacer portion 432,but not rotate relative thereto. Similarly, the rear spacer portion 438can also move axially relative to the forward spacer portion 432, butnot rotate relative to the forward spacer portion 432. As subsequentlydescribed in greater detail, the rotating shuttle 440 first rotates, andsubsequently translates.

According to one aspect, forward spacer portion 432 is fixedly securedto the stopper 434. One skilled in the art will understand that manymethods can be employed to secure the forward spacer portion 432 to thestopper 434, for example, adhesive, mechanical fasteners, or any othersuitable arrangement. Preferably, the forward spacer portion 432includes threads that engage mating threads in the stopper 434.

When the stopper spacer assembly 430 is screwed into the stopper 434, anaxial load is applied through access openings 442 in the rear spacerportion 438. This force can be used to push the stopper 434 forward,applying pressure to the fluid medicament. This pressure causes thefront (distal) face of the stopper 434 to deflect and press proximally,pushing back on the rear spacer portion 438 and rotating the rotatingshuttle into its “as assembled” condition. In other words, when amedicament barrel is filled with medicament and the system's plunger isapplying axial force to the medicament via the spacer assembly 430, thedistal face of the stopper 434 is deformed by the pressure of themedicament. During medicament delivery, pressure is applied by a driveassembly (via the plunger) to the rear spacer portion 438, which in turnapplies a rotational torque to the rotating shuttle 440 via helicalfaces 444 of the rear spacer portion 438. But the stopper deformationfrom the medicament provides a rearward or proximal force on the innerplunger 436, which prevents rotation of the rotating shuttle 440.

According to one aspect, an axial reaction load on the inner plunger 436can be increased by increasing the length of the inner plunger 436.

Once the medicament delivery is complete, as shown in FIG. 87, thepressure on the stopper 434 decreases, thereby permitting the distal endof the inner plunger 436 to displace distally. This distal displacementpermits the rotating shuttle 440 to rotate. The continued axial forceapplied by the drive assembly rotates and distally displaces therotating shuttle 440 due to interaction of the helical faces 444 in therear spacer portion 438 with corresponding cam-faced arms 446 of therotating shuttle 440. According to one aspect, this final movement ofthe rotating shuttle 440 causes the drive assembly to trigger needleretraction.

Referring to FIGS. 88-90, a spacer assembly 460 according to a furtheraspect of the present invention is shown. The spacer assembly 460 shownin FIGS. 88-90 allows for the removal of the effect of manufacturingtolerance build up through adjustment of the spacer assembly therebyallowing each system to inject the same amount of medicament.

As shown in FIG. 89, the spacer assembly 460 includes a stopper 462 anda stopper spacer 464. The stopper spacer 464 includes a fixed spacerpiece or fixed spacer 466 that is fixedly connected with the stopper462, and an adjustable spacer piece or adjustable spacer 468 that isrotationally displaceable in one direction relative to the fixed spacer466.

One skilled in the art will understand that many methods can be employedto secure the fixed spacer 466 to the stopper 462, for example,adhesive, mechanical fasteners, or any other suitable arrangement.Preferably, the fixed spacer 466 includes one or more external threadsthat engage one or more mating threads in the stopper 462. According toone aspect, the adjustable spacer 468 has a distal stem with an externalthread 470. The distal stem thread 470 engages an internal thread 472 inthe fixed spacer 466 (best shown in FIG. 90) to rotationally controlaxial displacement of the adjustable spacer 468 relative to the fixedspacer 466.

As shown in FIGS. 88 and 89, the fixed spacer 466 includes radiallyspaced detents 474 and the adjustable spacer 468 includes a springdetent arm 476, the free end of which engages a selected one of thedetents 474 to prevent rotation and axial displacement of the adjustablespacer 468 toward the fixed spacer 466. The free end of the springdetent arm 476 is shaped to pass over the detents 474 in one direction,thereby permitting rotation and proximal axial displacement of theadjustable spacer 468 away from the fixed spacer 466.

Despite variations in the dimensions of stoppers and containers, theadjustable spacer 468 can be adjusted relative to the fixed spacer 466to provide a consistent axial length of the stopper assembly 460.

As shown in FIG. 90, once the container is filled, an axial load, suchas a load that would be encountered when installed in the system 10,200, can be applied to the adjustable spacer 468 (and thus, the fixedspacer 466 and the stopper 462). Once the axial load is applied, theadjustable spacer 468 can be proximally backed out to ensure aconsistent gap 478 between the proximal end of a medicament barrel 480and the proximal face of the adjustable spacer 468, thereby accountingfor variations in the medicament barrel glass and the compressibility ofany entrapped air. In other words, the spacer assembly 460 allows theadjustable spacer 468 to have a predetermined set position relative tothe container 14 independent of the variables of the container 14 andstopper length. Accordingly, the start position of the spacer assembly460 is a predetermined distance from the container 14 and the endposition of the spacer assembly 460 is also a predetermined distancefrom the container 14 such that the travel of the stopper 462 is definedby the effective length of the plungers 52, 54 of the drive assembly 12.

Referring to FIGS. 91 and 92, a base column 482 and a cap 484 of anautomatically adjusting spacer 486 according to one aspect of thepresent invention is shown. The base column 482 includes a base portion488 and an axially extending column 490. According to one embodiment,the base column 482 includes a plurality of columnar protrusions 491that each have a plurality of ratchet teeth 492 disposed on a proximalportion thereof. A locking barb 493 is disposed at the proximal end ofeach of the plurality of ratchet teeth 492. The cap 484 is hollow, and adistal end of the cap 484 includes one or more axial springs 494.According to one aspect, the axial springs 494 are bent, cantileveredarms formed during molding of the cap 484. According to another aspect,a separate biasing member, such as a compression spring can be employedin the automatically adjusting spacer 486. When assembled with the basecolumn 482, the springs 494 engage the base portion 488 and maintain aninitial spacing between the base column 482 and the cap 484. Accordingto one aspect, the springs 494 are omitted. The cap 484 also includes aplurality of flexible cantilevered arms or tabs 496, which each have afree proximal portion with a plurality internal of ratchet teeth 497.The proximal end of each flexible tab 496 includes a foot 498.

FIGS. 93A and 93B illustrate the cap of the automatically adjustingspacer deployed within a proximal recess of a stopper 499 at a proximalportion of a medicament barrel. The base column 482 is assembled intothe hollow cap 484 with the base portion 482 engaging the stopper 499and the feet 498 disposed outside the proximal end of the barrel.

In operation, as shown in FIGS. 93A and 93B, the cap 484 displacesdistally relative to the base column 482 (as well as the stopper 499 andthe barrel) until the proximal end of the cap 484 is flush with the endof the medicament barrel. This action causes the feet 498 to engage theinternal surface of the barrel and displace radially inward, therebyforcing the ratchet teeth 492 into locking engagement with the ratchetteeth 497. The locking barb 493, the engagement of the ratchet teeth 492and 497, and the engagement of the feet 498 with the internal surface ofthe barrel prevents the displacement of the cap 484 relative to the basecolumn 482. Thus, the automatically adjusting spacer 486 can accommodatedifferences in stoppers, barrel diameters, and medicament fill volumes,to automatically provide a bearing surface flush the proximal end of themedicament barrel.

Referring to FIGS. 94-100, a spacer assembly 660 according to a furtheraspect of the present invention is shown. The spacer assembly 660 issimilar to the spacer assembly 460 discussed above and shown in FIGS.76-78 and operates in a similar manner to achieve similar advantages.The spacer assembly 660 includes a fixed spacer 666 and an adjustablespacer 668. The fixed spacer 666 is configured to be received by thestopper 462 with lugs 670 engaging the stopper 462 to secure the fixedspacer 666 within the stopper 462, although other suitable securingarrangements, such as threads, may be utilized. The fixed spacer 666includes interior threads 672 that receive exterior threads 678 of theadjustable spacer 668. The fixed spacer 666 includes a plurality ofdetents 674 positioned on a helical portion of the fixed spacer 666. Theadjustable spacer 668 includes a spring detent arm 676 that engages oneof the detents 674 to prevent rotation and axial displacement of theadjustable spacer 668 relative toward the fixed spacer 666. The springdetent arm 676 is shaped and configured to pass over the detents 674 inone direction to allow rotation and axial displacement of the adjustablespacer 668 away from the fixed spacer 666. The adjustable spacer 668 maybe initially secured to the fixed spacer 666 via the threads 672, 678 byapplying a force to the top of the spring detent arm 676, which biasesthe spring detent arm 676 away from the detents 674 to allow the spacers666, 668 to be secured to each other. Accordingly, in the same manner asdiscussed above in connection with spacer assembly 460, the adjustablespacer is free to rotate in one axial direction to adjust the length ofthe spacer assembly 660.

Referring again to FIGS. 94-100, the spacer assembly 660 furtherincludes a shim 680 configured to be received and secured to theadjustable spacer 668. Rather than providing a plurality of sizes ofadjustable spacers 468, 668, a plurality of shim 680 sizes can beprovided to accommodate a plurality of different fill volumes within thecontainer 14. The shim 680 may be secured to the adjustable spacer 668via a connector 682 extending from the shim 680 that is received by theadjustable spacer 668 using a snap-fit, although other suitable securingarrangements may be utilized. A center portion 684 of the fixed spacer666 is configured to be engaged while the adjustable spacer 668 isrotated relative to the fixed spacer 666 to prevent rotation of thefixed spacer 666 along with the adjustable spacer 668. The centerportion 684 of the fixed spacer 666 is accessible through an opening inthe shim 680.

Referring to FIGS. 101-103, a spacer assembly 700 according to a furtheraspect of the present invention is shown. The spacer assembly 700 has aspacer 702 and shims 704. The spacer 702 has a central column 706 and aproximal flange 708. The central column 706 is received within andattached to the stopper 710 of the container 712 such that the proximalflange 708 abuts the proximal end of the stopper 710. The spacer 702 maybe attached to the stopper 710 using any suitable method including, butnot limited to, adhesive, a threaded connection, and a snap-fitconnection. Rather than providing spacers 702 having proximal flanges708 of different thicknesses, a plurality of shims 704 having differentsizes are provided to accommodate a plurality of different fill volumeswithin the container 712. The shims 704 may have a shape correspondingto the shape of the proximal flange 708 and may be secured to theproximal flange 708 via a snap-fit connection or an adhesive, althoughother suitable securing arrangements may be utilized. The sizes of theavailable shims 704 may be arranged in a binary fashion, i.e., eachsuccessively thicker shim 704 is twice as thick as the previous shim704, as shown in FIG. 103. The shims 704 may be attached to the spacer702 before it is attached to the stopper 710 and/or after it is attachedto the stopper 710.

Referring to FIGS. 104 and 105, a spacer assembly 800 according to afurther aspect of the present invention is shown. The spacer assembly800 has a movable spacer 802 and a fixed spacer holder 804. The spacer802 has a central column 806 and a proximal flange 808. The spacerholder 804 is received by the stopper 810 and has a central cavity 812that receives the central column 806 of the spacer 802. The spacerholder 804 may be fixedly attached to the stopper 810 using any suitablemethod including, but not limited to, adhesive, a threaded connection,and a snap-fit connection. An adhesive 814 attaches the outer surface ofthe sidewall 816 of the central column 806 to the inner surface of thesidewall 818 of the central cavity 812 of the spacer holder 804. Theadhesive 814 may be any suitable adhesive including, but not limited to,contact adhesive, UV curable adhesive, and a laser curable adhesive. Asshown in FIG. 104, the inner surface of sidewall 818 of the centralcavity 812 of the spacer holder 804 may include a threaded portion 820that engages a corresponding threaded portion 822 in the outer surfaceof the sidewall 816 of the central column 806 of the spacer 802. Theadhesive may be provided on the threaded portion of the spacer 802and/or the spacer holder 804. After the spacer 802 is threaded into thecentral cavity 812 of the spacer holder 804 and the desired length ofthe spacer assembly 800 is set, the adhesive 814 is cured attaching thespacer 802 to the spacer holder 804, thereby fixing the length of thespacer assembly 800. Alternatively, as shown in FIG. 105, a laser orultrasonic weld 824 may be used to attach the spacer 802 to the spacerholder 804, thereby fixing the length of the spacer assembly 800. Thespacer 802 may be transparent while the spacer holder is opaque.

Referring to FIG. 106, a spacer assembly 900 according to a furtheraspect of the present invention is shown. The spacer assembly 900 has aspacer 902 and a spacer holder 904. The spacer 902 has a central column906 and a proximal flange 908. The spacer holder 904 is received by thestopper 910 and has a central cavity 912 that receives the centralcolumn 906 of the spacer 902. The spacer holder 904 may be attached tothe stopper 910 using any suitable method including, but not limited to,adhesive, a threaded connection, and a snap-fit connection. Anultrasonic or laser weld 914 attaches the outer distal surface 916 ofthe central column 906 to the inner bottom surface 918 of the centralcavity 912 of the spacer holder 904 locking the positon of the spacer902 with respect to the spacer holder 904, thereby fixing the length ofthe spacer assembly 900. The height of the spacer 902 may be adjustedrelative to the spacer holder 904 to provide an infinite number ofheight increments.

Referring to FIGS. 107 and 108, a spacer assembly 1000 according to afurther aspect of the present invention is shown. The spacer assembly1000 has a spacer 1002 and a spacer holder 1004. The spacer 1002 has acentral column 1006 and a proximal flange 1008. The spacer holder 1004is received by the stopper 1010 and comprises a sidewall 1012 extendingin a proximal direction from a bottom portion 1014. The sidewall 1012and the bottom portion 1014 define a central cavity 1016 that receivesthe central column 1006 of the spacer 1002. The spacer holder 1004 maybe attached to the stopper 1010 using any suitable method including, butnot limited to, adhesive, a threaded connection, and a snap-fitconnection. The inner surface of sidewall 1012 of the spacer holder 1004includes a threaded portion 1018 that engages a corresponding threadedportion 1020 in the outer surface of the central column 1006 of thespacer 1002. As shown in FIG. 107, the proximal end surface of thesidewall 1012 of the spacer holder 1004 includes a plurality of ratchetteeth configured to engage a flexible tab 1024 that extends axially in adistal direction from the proximal flange 1008 of the spacer 1002. Theproximal end surface of the sidewall 1012 of the spacer holder 1004 onwhich the ratchet teeth are positioned is angled in a distal directionaround the circumference of the sidewall 1012 to assure that, as thecentral column 1006 of the spacer 1002 is threaded into the centralcavity 1016 of the spacer holder 1004, the flexible tab 1024 staysengaged with the ratchet teeth. The engagement between the ratchet teethon the spacer holder 1004 and the flexible tab 1024 only allows thespacer 1002 to be rotated in one direction with respect to the spacerholder 1004. As a result, the central column 1006 of the spacer 1002 maybe threaded into the central cavity 1016 of the spacer holder 1004, butis kept from being unthreaded from the central cavity 1016 of the spacerholder 1004 by the locking engagement of between the ratchet teeth andthe flexible tab 1024.

Alternatively, as shown in FIG. 108, a flange 1026 may extend from theproximal end surface of the sidewall 1012 of the spacer holder 1004. Theflange 1026 includes a plurality of ratchet teeth configured to engage aflexible tab 1028 that extends in a radial direction from the proximalflange 1008 of the spacer 1002. The flange 1026 on which the ratchetteeth are positioned is configured around the circumference of thesidewall 1012 of the spacer holder 1004 to assure that, as the centralcolumn 1006 of the spacer 1002 is threaded into the central cavity 1016of the spacer holder 1004, the flexible tab 1028 stays engaged with theratchet teeth.

The bottom portion 1014 of the spacer holder 1004 may be provided at avariety of thicknesses as shown in FIG. 107 in order to provide anotherdimension of adjustability for containers having different fill volumes.

Referring to FIGS. 109 and 110, a spacer assembly 1100 according to afurther aspect of the present invention is shown. The spacer assembly1100 has a spacer 1102 and a spacer holder 1104. The spacer 1102 has acentral column 1106 and a proximal flange 1108. The spacer holder 1104is received by the stopper 1110 and comprises a sidewall 1112 extendingin a proximal direction from a bottom portion 1114. The sidewall 1112and the bottom portion 1114 define a central cavity 1116 that receivesthe central column 1106 of the spacer 1102. The spacer holder 1104 maybe attached to the stopper 1010 using any suitable method including, butnot limited to, adhesive, a threaded connection, and a snap-fitconnection. The spacer 1102 includes a protrusion 1118 extending axiallyin a distal direction from the proximal bottom surface 1120 of thecentral column 1106. The protrusion 1118 extends around less than halfof the circumference of the proximal bottom surface 1120 of the centralcolumn 1106. The spacer holder 1104 includes a protrusion 1122 extendingaxially into the central cavity 1116 from the bottom portion 1114 of thespacer holder 1104. The protrusion 1122 extends around less than half ofthe circumference of the bottom portion 1114 of the spacer holder 1004.When the spacer 1102 is in a first position, as shown in FIG. 109, theprotrusion 1118 on the spacer 1102 contacts the bottom portion 1114 ofthe spacer holder 1104 and the protrusion 1122 on the spacer holder 1104contacts the proximal bottom surface 1120 of the spacer 1102 such thatthe spacer assembly has a first length. When the spacer 1102 is in asecond position, as shown in FIG. 110, the protrusion 1118 on the spacer1102 contacts the protrusion 1122 on the spacer holder 1104 such thatthe spacer assembly has a second length that is greater than the firstlength. While a specific embodiment using a spacer and a spacer holderhaving configurations that allow for the length of the spacer assemblyto be changed based on the relative position of the spacer to the spacerholder has been described, other similar configurations may also beutilized.

Referring to FIG. 111, a spacer assembly 1200 according to a furtheraspect of the present invention is shown. The spacer assembly 1200 has aspacer 1202 and a spacer holder 1204. The spacer 1202 has a centralcolumn 1206 and a proximal flange 1208. The spacer holder 1204 isreceived by the stopper 1210 and comprises a sidewall 1212 extending ina proximal direction from a bottom portion 1214. The sidewall 1212 andthe bottom portion 1214 define a central cavity 1216 that receives thecentral column 1206 of the spacer 1202. The spacer holder 1204 may beattached to the stopper 1210 using any suitable method including, butnot limited to, adhesive, a threaded connection, and a snap-fitconnection. The inner surface of sidewall 1212 of the spacer holder 1204includes a non-overhauling threaded portion 1218 that engages acorresponding non-overhauling threaded portion 1220 in the outer surfaceof the central column 1206 of the spacer 1202. A non-overhauling threadas used herein results in a threaded connection where application oftorque to the first component of the threaded system will cause thefirst component to rotate with respect to the second component, but noamount of axial force applied to the first component will cause it torotate with respect to the second component. In the present embodiment,the threaded portion 1220 of the central column 1206 of the spacer 1202and the threaded portion 1218 of the sidewall 1212 of the spacer holder1204 are configured such that after torque is applied to the spacer 1202to threadingly attach it to the spacer holder 1204, application of asubsequent axial force will not cause the spacer 1202 to turn withrespect to the spacer holder 1204. At least a portion of the threadedportion 1220 in the outer surface of the central column 1206 of thespacer 1202 may have threads that extend radially outward to increasethe locking engagement between the threaded portion 1218 of the spacerholder 1204 and the threaded portion 1220 of the spacer 1202. Inaddition or alternatively, as shown in FIG. 112, the threaded portion1220 of the spacer may have threads 1224 with an upper outer face 1226that is angled downward in the proximal direction and a bottom outerface 1228 that extends in a radial direction forming a pointedtooth-shaped structure. When an axial force in the distal direction, asshown by the arrow 1230, is placed on the spacer 1202 in order to movethe stopper 1210 in the distal direction, the pointed threads 1224 diginto the sidewall 1212 of the spacer holder 1204 to lock the spacer 1202to the spacer holder 1204.

Referring to FIGS. 113-115, a spacer assembly 1300 according to afurther aspect of the present invention is shown. The spacer assembly1300 has a spacer 1302 and a spacer holder 1304. The spacer 1302 has anannular ring 1306 extending from a proximal flange 1308. The spacerholder 1304 is received by the stopper 1310 and comprises a sidewall1312 and a central post 1314 both extending in a proximal direction froma bottom portion 1316. The sidewall 1312, the central post 1314, and thebottom portion 1316 define an annular cavity 1318 that receives theannular ring 1306 of the spacer 1302. The spacer holder 1304 may beattached to the stopper 1310 using any suitable method including, butnot limited to, adhesive, a threaded connection, and a snap-fitconnection. The inner surface of the sidewall 1312 of the spacer holder1304 includes an overhauling threaded portion 1320 that engages acorresponding overhauling threaded portion 1322 in the outer surface ofthe annular ring 1306 of the spacer 1302, and the outer surface of thecentral post 1314 includes a non-overhauling threaded portion 1324 thatengages a corresponding non-overhauling threaded portion 1326 in theinner surface of the annular ring 1306 of the spacer 1302. Anon-overhauling threaded portion as used herein results in a threadedconnection where application of torque to a first component of thethreaded system will cause the first component to rotate with respect tothe second component, but no amount of axial force applied to the firstcomponent will cause it to rotate with respect to the second component.An overhauling threaded portion as used herein results in a threadedconnection where application of either torque or an axial force to afirst component of the threaded system will cause the component torotate with respect to the second component. The threads of theoverhauling threaded portions and the threads of the non-overhaulingthreaded portions may have the same pitch.

In the present embodiment, as shown in FIG. 113, when a proximal axialforce, indicated by arrow 1328, is applied the central post 1314, theload path for a distal axial force, indicated by arrow 1330, is directedthrough the overhauling threaded connection between the overhaulingthreaded portion 1320 in the inner surface of the sidewall 1312 of thespacer holder 1304 and the overhauling threaded portion 1322 in theouter surface of the annular ring 1306 of the spacer 1302. Because thisthreaded connection has overhauling threads, the axial force 1330 causesthe spacer 1302 to rotate and thread into the annular cavity 1318 of thespacer holder 1304. When the force 1328 is released, the load path foran axial force 1330 is directed through the non-overhauling threadedconnection between the non-overhauling threaded portion 1324 in theouter surface of the central post 1314 of the spacer holder 1304 and thenon-overhauling threaded portion 1326 in the inner surface of theannular ring 1306 of the spacer 1302 (FIG. 114). Because this threadedconnection has non-overhauling threads, the axial force 1330 does notcause the spacer 1302 to rotate such that movement of the spacer 1302with respect to the spacer holder 1304 is restricted.

FIGS. 115A-115C show how the spacer assembly 1300 is assembled. In afirst step, shown in FIG. 115A, a distal axial force, indicated by arrow1332, is applied to the proximal end of the sidewall 1312 of the spacerholder 1304 and a proximal axial force, indicated by arrow 1334, isapplied to the central post 1314. A fixture 1336 is then used to apply aproximal axial force, indicated by arrow 1338, to the proximal flange1308 of the spacer 1302 (FIG. 115B). The fixture 1336 has bearingsurfaces 1340 that contact the proximal flange 1308 of the spacer 1302allowing the spacer 1302 to rotate. When a distally extending flange1342 on the fixture 1336 contacts the proximal end 1344 of the container1344, the rotation of the spacer 1302 stops as the proximal axial load1338 is transferred to the container 1344 (FIG. 115C).

Referring to FIGS. 116 and 117, a spacer assembly 1400 according to afurther aspect of the present invention is shown. The spacer assembly1400 has a spacer 1402, a spacer holder 1404, and a locking pin 1406.The spacer 1402 has a sidewall 1408 extending in a proximal directionfrom a bottom portion 1410 and a proximal flange 1412. The sidewall 1408and the bottom portion 1410 define a recess 1414 that receives thelocking pin 1406. The spacer holder 1404 is received by the stopper 1416and comprises a sidewall 1418 extending in a proximal direction from abottom portion 1420. The sidewall 1418 and the bottom portion 1420define a central cavity 1422 that receives the spacer 1402. The spacerholder 1404 may be attached to the stopper 1416 using any suitablemethod including, but not limited to, adhesive, a threaded connection,and a snap-fit connection. The inner surface of sidewall 1418 of thespacer holder 1404 includes a threaded portion 1424 that engages acorresponding threaded portion 1426 in the outer surface of the sidewall1408 of the spacer 1402. After the spacer 1402 is threaded into thecentral cavity 1422 of the spacer holder 1404 such that the spacerassembly 1400 has the desired length, the locking pin 1406 is insertedinto the recess 1414 of the spacer 1402. The locking pin 1406 hassubstantially the same shape as the recess 1414 of the spacer 1402. Thelocking pin 1406 keeps the threaded portion 1426 of the sidewall 1408 ofthe spacer 1402 in good contact with the threaded portion 1424 of thesidewall 1418 of the spacer holder 1404, thereby creating a lockingengagement between the sidewall 1408 of the spacer 1402 and the sidewall1418 of the spacer holder 1404.

Referring to FIG. 118, a spacer assembly 1500 according to a furtheraspect of the present invention is shown. The spacer assembly 1500 has aspacer 1502, a spacer holder 1504, and an expandable container 1506. Thespacer 1502 has a sidewall 1508 extending in a distal direction from aproximal flange 1510. The spacer holder 1504 is received by the stopper1512 and comprises a sidewall 1514 extending in a proximal directionfrom a bottom portion 1516. The sidewall 1514 and the bottom portion1516 define a central cavity 1518 that receives the sidewall 1508 of thespacer 1502. The spacer holder 1504 may be attached to the stopper 1512using any suitable method including, but not limited to, adhesive, athreaded connection, and a snap-fit connection. An opening having avalve 1520 extends through the proximal flange 1510 of the spacer 1502and into the expandable container 1506. The expandable container 1506may be filled with air or any other suitable fluid via the valve 1520 inorder to change the distance that the proximal flange 1510 is separatedfrom the proximal end of the sidewall 1514 of the spacer holder 1504,thereby changing the length of the spacer assembly 1600.

An adjustable plunger assembly 1700 may be provided as an alternative toan adjustable spacer assembly. In this embodiment, shown in FIG. 119,the container remains stationary and the valve assembly is configured topierce the septum without any movement of the container. A singleplunger assembly 1700 comprising a plunger 1702 having a centralpassageway 1704, a plunger extension 1706, and a biasing member 1708 isprovided. The inner surface of the central passageway 1704 includes athreaded portion 1710 that engages a corresponding threaded portion 1712in the outer surface of the plunger extension 1706. During assembly ofthe drug delivery system, the distance that the plunger extension 1706extends beyond the distal end 1714 of the plunger 1702 can be changed byadjusting the length of the plunger extension 1706 that is inserted intothe central passageway 1704 of the plunger 1702. The plunger assembly1700 is adjusted by rotating the plunger extension 1706 until the distalend 1716 of the plunger extension 1706 contacts a standard spacer 1718attached to the stopper 1720. In this manner, the plunger extension 1706replaces the adjustable spacer assemblies described above while stillallowing containers having different fill volumes to be used.

Elements of one disclosed aspect can be combined with elements of one ormore other disclosed aspects to form different combinations, all ofwhich are considered to be within the scope of the present invention.

While this disclosure has been described as having exemplary designs,the present disclosure can be further modified within the spirit andscope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the disclosure using itsgeneral principles. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this disclosure pertains and which fallwithin the limits of the appended claims.

What is claimed is:
 1. A drive assembly for a drug delivery system, thedrive assembly comprising: a plunger member configured to engage andmove a stopper within a container, the plunger member having a firstposition and a second position axially spaced from the first position; abiasing member configured to move the plunger member from the firstposition to the second position; and an adjustable spacer assemblypositioned between the plunger member and the stopper.
 2. The assemblyof claim 1, wherein the spacer assembly comprises a spacer elementattached to the stopper and at least one shim.
 3. The assembly of claim1, wherein the spacer assembly comprises a spacer element and a holderto which the spacer element is attached.
 4. The assembly of claim 3,wherein the holder is attached to the stopper and the spacer element isattached to the holder by a threaded engagement.
 5. The assembly ofclaim 4, wherein the spacer assembly further comprises a flexible tabextending from the spacer element and a surface of the spacer holdercomprises a plurality of ratchet teeth, the flexible tab engaging theratchet teeth, wherein the engagement of the flexible tab with theratchet teeth allows the spacer element to be rotated in a directionthat threads the spacer element into the holder and prevents the spacerelement from rotating in a direction that removes the spacer elementfrom the holder.
 6. The assembly of claim 3, wherein when the spacerelement is in a first position with respect to the holder, the spacerassembly has a first length in a longitudinal direction, and when thespacer element is in a second position with respect to the holder, thespacer assembly has a second length in the longitudinal direction, thefirst length being greater than the second length.
 7. The assembly ofclaim 6, wherein the spacer element comprises a first protrusion and theholder comprises a second protrusion and when the spacer element is inthe first position with respect to the holder, the first protrusion isin contact with the second protrusion and the spacer assembly has thefirst length in the longitudinal direction, and when the spacer elementis in a second position with respect to the holder, the first protrusionis not in contact with the second protrusion and the spacer assembly hasthe second length in the longitudinal direction.
 8. The assembly ofclaim 4, wherein the threaded engagement allows rotation of the spacerelement relative to the holder when a torque is applied to the spacerelement and prevents rotation of the spacer element relative to theholder when an axial force is applied to the spacer element.
 9. Theassembly of claim 8, wherein threads provided on the spacer elementextend in a radially outward direction.
 10. The assembly of claim 8,wherein threads provided on the spacer element are angled such thatapplication of an axial force to the spacer element causes the threadsto engage a sidewall of the holder.
 11. The assembly of claim 3, whereinthe spacer element comprises an annular sidewall, the holder comprises asidewall and a central post, and wherein an exterior surface of theannular sidewall of the spacer element is in threaded engagement with aninterior surface of the sidewall of the holder, and an interior surfaceof the sidewall of the spacer is in threaded engagement with an exteriorsurface of the central post.
 12. The assembly of claim 11, wherein whenthe central post is a first position, movement of the spacer elementwith respect to the holder is prohibited, and when the central post isaxially extended to a second position, the spacer element is free torotate with respect to the holder.
 13. The assembly of claim 4, whereinthe spacer assembly further comprises a locking pin and the spacerelement further comprises a recess for receiving the locking pin. 14.The assembly of claim 3, wherein the spacer assembly further comprisesan expandable container positioned within the spacer element and theholder between an upper proximal portion of the spacer element and alower bottom portion of the holder.
 15. The assembly of claim 14,wherein expansion or contraction of the expandable container causes thespacer element to move relative to the holder.
 16. The assembly of claim4, wherein the spacer assembly comprises a spacer element fixed to thestopper and a plunger extension movably fixed to the plunger member. 17.The assembly of claim 16, wherein the plunger extension is in threadedengagement with the plunger member.
 18. A drug delivery system forinjecting a medicament, the system comprising: a container configured toreceive a medicament, the container comprising a stopper configured tomove within the container and a closure; a drive assembly comprising: aplunger member configured to engage and move the stopper within thecontainer, the plunger member having a first position and a secondposition axially spaced from the first position; a biasing memberconfigured to move the plunger member from the first position to thesecond position; and an adjustable spacer assembly positioned betweenthe plunger member and the stopper; and a needle actuator assemblycomprising a needle configured to be placed in fluid communication withthe container.
 19. The system of claim 18, wherein the spacer assemblycomprises a spacer element and a holder to which the spacer element isattached.
 20. The system of claim 19, wherein the holder is attached tothe stopper and the spacer element is attached to the holder by athreaded engagement.
 21. The system of claim 18, wherein the spacerassembly comprises a spacer element fixed to the stopper and a plungerextension movably fixed to the plunger member.